• Cahill, D. G. Analysis of heat flow in layered structures for time-domain thermoreflectance. Rev. Sci. Instrum. 75, 5119–5122 (2004). This work presents an introduction to and a description of the now-standardized TDTR experimental layout and data analysis, including out-of-phase signals.

    ADS 

    Google Scholar
     

  • Cahill, D. G., Goodson, K. & Majumdar, A. Thermometry and thermal transport in micro/nanoscale solid-state devices and structures. J. Heat. Transf. 124, 223–241 (2002).


    Google Scholar
     

  • Rosei, R. & Lynch, D. W. Thermomodulation spectra of Al, Au, and Cu. Phys. Rev. B 5, 3883–3894 (1972).

    ADS 

    Google Scholar
     

  • Rosei, R. Temperature modulation of the optical transitions involving the Fermi surface in Ag: theory. Phys. Rev. B 10, 474–483 (1974).

    ADS 

    Google Scholar
     

  • Weaver, J. H., Lynch, D. W., Culp, C. H. & Rosei, R. Thermoreflectance of V, Nb, and paramagnetic Cr. Phys. Rev. B 14, 459–463 (1976).

    ADS 

    Google Scholar
     

  • Colavita, E., Franciosi, A., Mariani, C. & Rosei, R. Thermoreflectance test of W, Mo and paramagnetic Cr band structures. Phys. Rev. B 27, 4684–4693 (1983).

    ADS 

    Google Scholar
     

  • Braun, J. L. & Hopkins, P. E. Upper limit to the thermal penetration depth during modulated heating of multilayer thin films with pulsed and continuous wave lasers: a numerical study. J. Appl. Phys. 121, 175107 (2017).

    ADS 

    Google Scholar
     

  • Chen, G. Nanoscale Energy Transport and Conversion: A Parallel Treatment of Electrons, Molecules, Phonons, and Photons (Oxford Univ. Press, 2005).

  • Zhang, Z. Nano/Microscale Heat Transfer (McGraw-Hill, 2007).

  • Kaviany, M. Heat Transfer Physics (Cambridge Univ. Press, 2008).

  • Srivastava, G. P. The Physics of Phonons (Taylor and Francis, 1990).

  • Swartz, E. T. & Pohl, R. O. Thermal boundary resistance. Rev. Mod. Phys. 61, 605–668 (1989).

    ADS 

    Google Scholar
     

  • Hopkins, P. E. Thermal transport across solid interfaces with nanoscale imperfections: effects of roughness, disorder, dislocations, and bonding on thermal boundary conductance. ISRN Mech. Eng. 2013, 1–19 (2013).

    ADS 

    Google Scholar
     

  • Monachon, C., Weber, L. & Dames, C. Thermal boundary conductance: a materials science perspective. Annu. Rev. Mater. Res. 46, 433 (2016).

    ADS 

    Google Scholar
     

  • López-Honorato, E. et al. Thermal conductivity mapping of pyrolytic carbon and silicon carbide coatings on simulated fuel particles by time-domain thermoreflectance. J. Nucl. Mater. 378, 35–39 (2008).

    ADS 

    Google Scholar
     

  • Zhao, J.-C., Zheng, X. & Cahill, D. G. High-throughput diffusion multiples. Mater. Today 8, 28–37 (2005). This work demonstrates using TDTR to spatially map the thermal conductivity of materials.


    Google Scholar
     

  • Olson, D. H. et al. Anisotropic thermal conductivity tensor of β-Y2Si2O7 for orientational control of heat flow on micrometer scales. Acta Mater. 189, 299–305 (2020).

    ADS 

    Google Scholar
     

  • Olson, D. H. et al. Evolution of microstructure and thermal conductivity of multifunctional environmental barrier coating systems. Mater. Today Phys. 17, 100304 (2021).


    Google Scholar
     

  • Olson, D. H. et al. Local thermal conductivity measurements to determine the fraction of α-cristobalite in thermally grown oxides for aerospace applications. Scr. Mater. 177, 214–217 (2020).


    Google Scholar
     

  • Milich, M. et al. Quantifying devitrification and porosity in thermally grown oxides through spatially-resolved time-domain thermoreflectance. Acta Mater. 288, 120802 (2025).


    Google Scholar
     

  • Ardrey, K. D. et al. Opportunities for novel refractory alloy thermal/environmental barrier coatings using multicomponent rare earth oxides. Scr. Mater. 251, 116206 (2024).


    Google Scholar
     

  • Koh, Y. K., Bae, M.-H., Cahill, D. G. & Pop, E. Heat conduction across monolayer and few-layer graphenes. Nano Lett. 10, 4363–4368 (2010).

    ADS 

    Google Scholar
     

  • Liu, H. et al. Spontaneous chemical functionalization via coordination of Au single atoms on monolayer MoS2. Sci. Adv. 6, eabc9308 (2020).

    ADS 

    Google Scholar
     

  • Zhang, F. et al. Monolayer vanadium-doped tungsten disulfide: a room-temperature dilute magnetic semiconductor. Adv. Sci. 7, 2001174 (2020).


    Google Scholar
     

  • Evans, A. M. et al. Thermally conductive ultra-low-k dielectric layers based on two-dimensional covalent organic frameworks. Nat. Mater. 20, 1142–1148 (2021).

    ADS 

    Google Scholar
     

  • Cancellieri, C. et al. Interface and layer periodicity effects on the thermal conductivity of copper-based nanomultilayers with tungsten, tantalum, and tantalum nitride diffusion barriers. J. Appl. Phys. 128, 195302 (2020).

    ADS 

    Google Scholar
     

  • Cheaito, R. et al. Interplay between total thickness and period thickness in the phonon thermal conductivity of superlattices from the nanoscale to the microscale: coherent versus incoherent phonon transport. Phys. Rev. B 97, 085306 (2018).

    ADS 

    Google Scholar
     

  • Lorenzin, G. et al. Tensile and compressive stresses in Cu/W multilayers: correlation with microstructure, thermal stability, and thermal conductivity. Acta Mater. 240, 118315 (2022).


    Google Scholar
     

  • Ravichandran, J. et al. Crossover from incoherent to coherent phonon scattering in epitaxial oxide superlattices. Nat. Mater. 13, 168–172 (2014). This work discusses the implications of coherent phonon transport on the thermal conductivity of superlattices determined with TDTR.

    ADS 

    Google Scholar
     

  • Chen, P. et al. Role of surface-segregation-driven intermixing on the thermal transport through planar Si/Ge superlattices. Phys. Rev. Lett. 111, 115901 (2013).

    ADS 

    Google Scholar
     

  • Koh, Y. K., Cao, Y., Cahill, D. G. & Jena, D. Heat-transport mechanisms in superlattices. Adv. Funct. Mater. 19, 610–615 (2009).


    Google Scholar
     

  • Rawat, V., Koh, Y. K., Cahill, D. G. & Sands, T. D. Thermal conductivity of (Zr,W)N/ScN metal/semiconductor multilayers and superlattices. J. Appl. Phys. 105, 024909 (2009).

    ADS 

    Google Scholar
     

  • Babaei, H. et al. Observation of reduced thermal conductivity in a metal–organic framework due to the presence of adsorbates. Nat. Commun. 11, 4010 (2020).

    ADS 

    Google Scholar
     

  • Erickson, K. J. et al. Thin film thermoelectric metal–organic framework with high Seebeck coefficient and low thermal conductivity. Adv. Mat. 27, 3453–3459 (2015).


    Google Scholar
     

  • DeCoster, M. E. et al. Hybridization from guest–host interactions reduces the thermal conductivity of metal–organic frameworks. J. Am. Chem. Soc. 144, 3603–3613 (2022).


    Google Scholar
     

  • Meirzadeh, E. et al. A few-layer covalent network of fullerenes. Nature 613, 71–76 (2023).

    ADS 

    Google Scholar
     

  • Hoque, M. S. B. et al. Ruddlesden–Popper chalcogenides push the limit of mechanical stiffness and glass-like thermal conductivity in crystals. Nat. Commun. 16, 6104 (2025).


    Google Scholar
     

  • Zhao, B. et al. Orientation-controlled anisotropy in single crystals of quasi-1D BaTiS3. Chem. Mater. 34, 5680–5689 (2022).


    Google Scholar
     

  • Dames, C. Ultrahigh thermal conductivity confirmed in boron arsenide. Science 361, 549–550 (2018).

    ADS 

    Google Scholar
     

  • Kang, J. S., Li, M., Wu, H., Nguyen, H. & Hu, Y. Experimental observation of high thermal conductivity in boron arsenide. Science 361, 575–578 (2018).

    ADS 

    Google Scholar
     

  • Tian, F. et al. Unusual high thermal conductivity in boron arsenide bulk crystals. Science 361, 582–585 (2018).

    ADS 

    Google Scholar
     

  • Wang, X., Ho, V., Segalman, R. A. & Cahill, D. G. Thermal conductivity of high-modulus polymer fibers. Macromolecules 46, 4937–4943 (2013).

    ADS 

    Google Scholar
     

  • Cahill, D. G. Extremes of heat conduction—pushing the boundaries of the thermal conductivity of materials. MRS Bull. 37, 855–863 (2012).

    MathSciNet 

    Google Scholar
     

  • Cahill, D. G. Thermal-conductivity measurement by time-domain thermoreflectance. MRS Bull. 43, 782–789 (2018).

    ADS 

    Google Scholar
     

  • Schmidt, A., Chiesa, M., Chen, X. & Chen, G. An optical pump–probe technique for measuring the thermal conductivity of liquids. Rev. Sci. Instrum. 79, 64902 (2008).


    Google Scholar
     

  • Foley, B. M. et al. Voltage-controlled bistable thermal conductivity in suspended ferroelectric thin-film membranes. ACS Appl. Mater. Interfaces 10, 25493–25501 (2018).


    Google Scholar
     

  • Ihlefeld, J. F. et al. Room-temperature voltage tunable phonon thermal conductivity via reconfigurable interfaces in ferroelectric thin films. Nano Lett. 15, 1791–1795 (2015). This work uses TDTR to measure the thermal conductivity of a ferroelectric thin film while an electric field is applied to modulate the thermal conductivity via ferroelastic domain wall switching.

    ADS 

    Google Scholar
     

  • Foley, B. M. et al. Modifying surface energy of graphene via plasma-based chemical functionalization to tune thermal and electrical transport at metal interfaces. Nano Lett. 15, 4876–4882 (2015).

    ADS 

    Google Scholar
     

  • Hopkins, P. E. et al. Measuring the thermal conductivity of porous, transparent SiO2 films with time domain thermoreflectance. J. Heat. Transf. 133, 61601 (2011).


    Google Scholar
     

  • Hopkins, P. E., Kaehr, B., Piekos, E. S., Dunphy, D. & Brinker, C. J. Minimum thermal conductivity considerations in aerogel thin films. J. Appl. Phys. 111, 113532 (2012).

    ADS 

    Google Scholar
     

  • Rosul, M. G. et al. Thermionic transport across gold-graphene-WSe2 van der Waals heterostructures. Sci. Adv. 5, eaax7827 (2019).

    ADS 

    Google Scholar
     

  • Koh, Y. K. et al. Role of remote interfacial phonon (RIP) scattering in heat transport across graphene/SiO2 interfaces. Nano Lett. 16, 6014–6020 (2016).

    ADS 

    Google Scholar
     

  • Cho, J. et al. Electrochemically tunable thermal conductivity of lithium cobalt oxide. Nat. Commun. 5, 4035 (2014). This work uses TDTR to measure the thermal conductivity of a cathode material while an electric field is applied to modulate the thermal conductivity via lithiation.

    ADS 

    Google Scholar
     

  • Eesley, G. L. Observation of nonequilibrium electron heating in copper. Phys. Rev. Lett. 51, 2140–2143 (1983). To our knowledge, this work presents the first demonstration of using pulsed lasers (~12 ps pulse width) in a transient thermoreflectance configuration to measure thermal properties of a material.

    ADS 

    Google Scholar
     

  • Eesley, G. L. Generation of nonequlibrium electron and lattice temperatures in copper by picosecond laser pulses. Phys. Rev. B 33, 2144–2151 (1986).

    ADS 

    Google Scholar
     

  • Paddock, C. A. & Eesley, G. L. Transient thermoreflectance from thin metal films. J. Appl. Phys. 60, 285–290 (1986).

    ADS 

    Google Scholar
     

  • Opsal, J., Rosencwaig, A. & Willenborg, D. L. Thermal-wave detection and thin-film thickness measurements with laser beam deflection. Appl. Opt. 22, 3169–3176 (1983).

    ADS 

    Google Scholar
     

  • Opsal, J. & Rosencwaig, A. Thermal and plasma wave depth profiling in silicon. Appl. Phys. Lett. 47, 498–500 (1985).

    ADS 

    Google Scholar
     

  • Thomsen, C. et al. Coherent phonon generation and detection by picosecond light pulses. Phys. Rev. Lett. 53, 989–992 (1984).

    ADS 

    Google Scholar
     

  • Stoner, R. J. & Maris, H. J. Kapitza conductance and heat flow between solids at temperatures from 50 to 300 K. Phys. Rev. B 48, 16373–16387 (1993).

    ADS 

    Google Scholar
     

  • Bonello, B., Perrin, B. & Rossignol, C. Photothermal properties of bulk and layered materials by the picosecond acoustics technique. J. Appl. Phys. 83, 3081–3088 (1998).

    ADS 

    Google Scholar
     

  • Capinski, W. S. & Maris, H. J. Improved apparatus for picosecond pump-and-probe optical measurements. Rev. Sci. Instrum. 67, 2720–2726 (1996).

    ADS 

    Google Scholar
     

  • Capinski, W. S. & Maris, H. J. Thermal conductivity of GaAs/AlAs superlattices. Phys. B 219–220, 699–701 (1996).

    ADS 

    Google Scholar
     

  • Capinski, W. S. et al. Thermal-conductivity measurements of GaAs/AlAs superlattices using a picosecond optical pump-and-probe technique. Phys. Rev. B 59, 8105–8113 (1999).

    ADS 

    Google Scholar
     

  • Huxtable, S., Cahill, D. G., Fauconnier, V., White, J. O. & Zhao, J. C. Thermal conductivity imaging at micrometre-scale resolution for combinatorial studies of materials. Nat. Mater. 3, 298–301 (2004).

    ADS 

    Google Scholar
     

  • Cahill, D. G. et al. Nanoscale thermal transport. J. Appl. Phys. 93, 793–818 (2003).

    ADS 

    Google Scholar
     

  • Costescu, R. M., Wall, M. A. & Cahill, D. G. Thermal conductance of epitaxial interfaces. Phys. Rev. B 67, 054302 (2003). This work demonstrates using TDTR to measure the thermal interface conductance.

    ADS 

    Google Scholar
     

  • Koh, Y. K. et al. Comparison of the 3ω method and time-domain thermoreflectance for measurements of the cross-plane thermal conductivity of epitaxial semiconductors. J. Appl. Phys. 105, 54303 (2009).


    Google Scholar
     

  • Jiang, P., Qian, X. & Yang, R. Tutorial: time-domain thermoreflectance (TDTR) for thermal property characterization of bulk and thin film materials. J. Appl. Phys. 28, 161103 (2018). This paper presents an extensive tutorial on TDTR.

    ADS 

    Google Scholar
     

  • Feser, J. P. & Cahill, D. G. Probing anisotropic heat transport using time-domain thermoreflectance with offset laser spots. Rev. Sci. Instrum. 83, 104901 (2012). This work uses a configuration of TDTR with offset pump and probe to measure both in-plane and out-of-plane thermal conductivity of materials.

    ADS 

    Google Scholar
     

  • Feser, J. P., Liu, J. & Cahill, D. G. Pump–probe measurements of the thermal conductivity tensor for materials lacking in-plane symmetry. Rev. Sci. Instrum. 85, 104903 (2014).

    ADS 

    Google Scholar
     

  • Kimling, J., Philippi-Kobs, A., Jacobsohn, J., Oepen, H. P. & Cahill, D. G. Thermal conductance of interfaces with amorphous SiO2 measured by time-resolved magneto-optic Kerr-effect thermometry. Phys. Rev. B 95, 184305 (2017).

    ADS 

    Google Scholar
     

  • Angeles, F. et al. Picosecond magneto-optic thermometry measurements of nanoscale thermal transport in AlN thin films. APL Mater. 11, 061127 (2023). This study presents an example of using TR-MOKE to interrogate the cross-plane thermal conductivity of high-k thin films.

    ADS 

    Google Scholar
     

  • Peng, W. & Wilson, R. B. Thermal model for time-domain thermoreflectance experiments in a laser-flash geometry. J. Appl. Phys. 131, 134301 (2022). This work discusses the laser-flash TDTR experiment and analyses.

    ADS 

    Google Scholar
     

  • Peng, W. & Wilson, R. B. Nanoscale laser flash measurements of diffuson transport in amorphous Ge and Si. APL Mater. 10, 041111 (2022).

    ADS 

    Google Scholar
     

  • Losego, M. D., Grady, M. E., Sottos, N. R., Cahill, D. G. & Braun, P. V. Effects of chemical bonding on heat transport across interfaces. Nat. Mater. 11, 502–506 (2012).

    ADS 

    Google Scholar
     

  • Zheng, X., Cahill, D. G. & Zhao, J.-C. Effect of MeV ion irradiation on the coefficient of thermal expansion of Fe–Ni invar alloys: a combinatorial study. Acta Mater. 58, 1236–1241 (2010).

    ADS 

    Google Scholar
     

  • Zheng, X., Cahill, D. G., Weaver, R. & Zhao, J.-C. Micron-scale measurements of the coefficient of thermal expansion by time-domain probe beam deflection. J. Appl. Phys. 104, 73509 (2008). This work presents as explanation of probe-beam deflection effects in TDTR experiments.


    Google Scholar
     

  • Tomko, J. A. et al. Nanoscale wetting and energy transmission at solid/liquid interfaces. Langmuir 35, 2106–2114 (2019).


    Google Scholar
     

  • Sun, J. et al. Probe beam deflection technique with liquid immersion for fast mapping of thermal conductance. Appl. Phys. Lett. 124, 42201 (2024).


    Google Scholar
     

  • Sun, J., Lv, G. & Cahill, D. G. Frequency-domain probe beam deflection method for measurement of thermal conductivity of materials on micron length scale. Rev. Sci. Instrum. 94, 14903 (2023).

    ADS 

    Google Scholar
     

  • Schmidt, A. J. Optical Characterization of Thermal Transport from the Nanoscale to the Macroscale (Massachusetts Institute of Technology, 2008).

  • Gomez, M. J., Liu, K., Lee, J. G. & Wilson, R. B. High sensitivity pump-probe measurements of magnetic, thermal, and acoustic phenomena with a spectrally tunable oscillator. Rev. Sci. Instrum. 91, 023905 (2020).

    ADS 

    Google Scholar
     

  • Liu, J., Choi, G.-M. & Cahill, D. G. Measurement of the anisotropic thermal conductivity of molybdenum disulfide by the time-resolved magneto-optic Kerr effect. J. Appl. Phys. 116, 233107 (2014).

    ADS 

    Google Scholar
     

  • Jang, H. et al. Thermal conductivity of oxide tunnel barriers in magnetic tunnel junctions measured by ultrafast thermoreflectance and magneto-optic Kerr effect thermometry. Phys. Rev. Appl. 13, 024007 (2020).

    ADS 

    Google Scholar
     

  • Wilson, R. B., Apgar, B. A., Martin, L. W. & Cahill, D. G. Thermoreflectance of metal transducers for optical pump–probe studies of thermal properties. Opt. Express 20, 28829–28838 (2012).

    ADS 

    Google Scholar
     

  • Hohensee, G. T., Hsieh, W. P., Losego, M. D. & Cahill, D. G. Interpreting picosecond acoustics in the case of low interface stiffness. Rev. Sci. Instrum. 83, 114902 (2012).

    ADS 

    Google Scholar
     

  • Wilson, R. B., Feser, J. P., Hohensee, G. T. & Cahill, D. G. Two-channel model for nonequilibrium thermal transport in pump–probe experiments. Phys. Rev. B 88, 144305 (2013).

    ADS 

    Google Scholar
     

  • Yang, J., Ziade, E. & Schmidt, A. J. Modeling optical absorption for thermoreflectance measurements. J. Appl. Phys. 119, 095107 (2016).

    ADS 

    Google Scholar
     

  • Hopkins, P. E. et al. Criteria for cross-plane dominated thermal transport in multilayer thin film systems during modulated laser heating. J. Heat. Transf. 132, 081302 (2010).


    Google Scholar
     

  • Schmidt, A. J., Chen, X. & Chen, G. Pulse accumulation, radial heat conduction, and anisotropic thermal conductivity in pump–probe transient thermoreflectance. Rev. Sci. Instrum. 79, 114902 (2008).

    ADS 

    Google Scholar
     

  • Wang, Y., Park, J. Y., Koh, Y. K. & Cahill, D. G. Thermoreflectance of metal transducers for time-domain thermoreflectance. J. Appl. Phys. 108, 43507 (2010).


    Google Scholar
     

  • Rosei, R., Colavita, E., Franciosi, A., Weaver, J. H. & Peterson, D. T. Electronic structure of the bcc transition metals: thermoreflectance studies of bulk V, Nb, Ta, and αTaHx. Phys. Rev. B 21, 3152–3157 (1980).

    ADS 

    Google Scholar
     

  • Islam, M. R. et al. Evaluating size effects on the thermal conductivity and electron-phonon scattering rates of copper thin films for experimental validation of Matthiessen’s rule. Nat. Commun. 15, 9167 (2024).


    Google Scholar
     

  • Yang, J., Ziade, E. & Schmidt, A. J. Uncertainty analysis of thermoreflectance measurements. Rev. Sci. Instrum. 87, 014901 (2016).

    ADS 

    Google Scholar
     

  • Khan, S., Shi, X., Feser, J. & Wilson, R. Thermal conductance of interfaces between titanium nitride and group IV semiconductors at high temperatures. Appl. Phys. Lett. 125, 041601 (2024).


    Google Scholar
     

  • Khan, S. et al. Properties for thermally conductive interfaces with wide band gap materials. ACS Appl. Mater. Interfaces 14, 36178–36188 (2022).


    Google Scholar
     

  • Jiang, P., Huang, B. & Koh, Y. K. Accurate measurements of cross-plane thermal conductivity of thin films by dual-frequency time-domain thermoreflectance (TDTR). Rev. Sci. Instrum. 87, 075101 (2016).

    ADS 

    Google Scholar
     

  • Kan, Y. K. Heat Transport by Phonons in Crystalline Materials and Nanostructures (Univ. of Illinois at Urbana-Champaign, 2010).

  • Cheng, Z. et al. Thermal visualization of buried interfaces enabled by ratio signal and steady-state heating of time-domain thermoreflectance. ACS Appl. Mater. Interfaces 13, 31843–31851 (2021).


    Google Scholar
     

  • Szwejkowski, C. J. et al. Size effects in the thermal conductivity of gallium oxide (β-Ga2O3) films grown via open-atmosphere annealing of gallium nitride. J. Appl. Phys. 117, 084308 (2015).

    ADS 

    Google Scholar
     

  • Aryana, K. et al. Interface controlled thermal resistances of ultra-thin chalcogenide-based phase change memory devices. Nat. Commun. 12, 774 (2021).

    ADS 

    Google Scholar
     

  • Lee, S.-M. & Cahill, D. G. Heat transport in thin dielectric films. J. Appl. Phys. 81, 2590–2595 (1997).

    ADS 

    Google Scholar
     

  • Jiang, P., Qian, X., Yang, R. & Lindsay, L. Anisotropic thermal transport in bulk hexagonal boron nitride. Phys. Rev. Mater. 2, 064005 (2018).


    Google Scholar
     

  • Jiang, P., Qian, X. & Yang, R. Time-domain thermoreflectance (TDTR) measurements of anisotropic thermal conductivity using a variable spot size approach. Rev. Sci. Instrum. 88, 074901 (2017).

    ADS 

    Google Scholar
     

  • Rai, A., Sangwan, V. K., Gish, J. T., Hersam, M. C. & Cahill, D. G. Anisotropic thermal conductivity of layered indium selenide. Appl. Phys. Lett. 118, 073101 (2021).

    ADS 

    Google Scholar
     

  • Jiang, P., Qian, X. & Yang, R. A new elliptical-beam method based on time-domain thermoreflectance (TDTR) to measure the in-plane anisotropic thermal conductivity and its comparison with the beam-offset method. Rev. Sci. Instrum. 89, 094902 (2018).

    ADS 

    Google Scholar
     

  • Zhu, J. et al. Revealing the origins of 3D anisotropic thermal conductivities of black phosphorus. Adv. Electron. Mater. 2, 1600040 (2016).


    Google Scholar
     

  • Jang, H., Wood, J. D., Ryder, C. R., Hersam, M. C. & Cahill, D. G. Anisotropic thermal conductivity of exfoliated black phosphorus. Adv. Mater. 27, 8017–8022 (2015).


    Google Scholar
     

  • Braun, J. L., Olson, D. H., Gaskins, J. T. & Hopkins, P. E. A steady-state thermoreflectance method to measure thermal conductivity. Rev. Sci. Instrum. 90, 24905 (2019). This work reviews SSTR.


    Google Scholar
     

  • Oh, D.-W., Ko, C., Ramanathan, S. & Cahill, D. G. Thermal conductivity and dynamic heat capacity across the metal-insulator transition in thin film VO2. Appl. Phys. Lett. 96, 151906 (2010).

    ADS 

    Google Scholar
     

  • Olson, D. H., Braun, J. L. & Hopkins, P. E. Spatially resolved thermoreflectance techniques for thermal conductivity measurements from the nanoscale to the mesoscale. J. Appl. Phys. 126, 150901 (2019).

    ADS 

    Google Scholar
     

  • Wang, X., Liman, C. D., Treat, N. D., Chabinyc, M. L. & Cahill, D. G. Ultralow thermal conductivity of fullerene derivatives. Phys. Rev. B 88, 075310 (2013).

    ADS 

    Google Scholar
     

  • Liu, J. et al. Simultaneous measurement of thermal conductivity and heat capacity of bulk and thin film materials using frequency-dependent transient thermoreflectance method. Rev. Sci. Instrum. 84, 034902 (2013). This study develops multi-frequency TDTR to measure both thermal conductivity and heat capacity.

    ADS 

    Google Scholar
     

  • Wei, C., Zheng, X., Cahill, D. G. & Zhao, J. C. Invited article: micron resolution spatially resolved measurement of heat capacity using dual-frequency time-domain thermoreflectance. Rev. Sci. Instrum. 84, 071301 (2013).

    ADS 

    Google Scholar
     

  • Wilson, R. B. et al. Electric current induced ultrafast demagnetization. Phys. Rev. B 96, 045105 (2017).

    ADS 

    Google Scholar
     

  • Qian, X., Zhou, J. & Chen, G. Phonon-engineered extreme thermal conductivity materials. Nat. Mater. 20, 1188–1202 (2021).

    ADS 

    Google Scholar
     

  • Cheng, Z., Graham, S., Amano, H. & Cahill, D. G. Perspective on thermal conductance across heterogeneously integrated interfaces for wide and ultrawide bandgap electronics. Appl. Phys. Lett. 120, 030501 (2022).

    ADS 

    Google Scholar
     

  • Zhang, Z. et al. Observation of thermal spin-transfer torque via ferromagnetic resonance in magnetic tunnel junctions. Phys. Rev. B 94, 064414 (2016).

    ADS 

    Google Scholar
     

  • Choi, G.-M., Wilson, R. B. & Cahill, D. G. Indirect heating of Pt by short-pulse laser irradiation of Au in a nanoscale Pt/Au bilayer. Phys. Rev. B 89, 064307 (2014).

    ADS 

    Google Scholar
     

  • Angeles, F., Shi, X. & Wilson, R. B. In situ and ex situ processes for synthesizing metal multilayers with electronically conductive interfaces. J. Appl. Phys. 131, 225302 (2022).

    ADS 

    Google Scholar
     

  • Choi, G.-M., Moon, C.-H., Min, B.-C., Lee, K.-J. & Cahill, D. G. Thermal spin-transfer torque driven by the spin-dependent Seebeck effect in metallic spin-valves. Nat. Phys. 11, 576–581 (2015).


    Google Scholar
     

  • Koh, Y. R. et al. Thermal boundary conductance across epitaxial metal/sapphire interfaces. Phys. Rev. B 102, 205304 (2020).

    ADS 

    Google Scholar
     

  • Kang, J. S. et al. Integration of boron arsenide cooling substrates into gallium nitride devices. Nat. Electron. 4, 416–423 (2021).


    Google Scholar
     

  • Cheng, Z. et al. High thermal conductivity in wafer-scale cubic silicon carbide crystals. Nat. Commun. 13, 7201 (2022).

    ADS 

    Google Scholar
     

  • Mu, F. et al. High thermal boundary conductance across bonded heterogeneous GaN–SiC interfaces. ACS Appl. Mater. Interfaces 11, 33428–33434 (2019).


    Google Scholar
     

  • Cheng, Z., Mu, F., Yates, L., Suga, T. & Graham, S. Interfacial thermal conductance across room-temperature-bonded GaN/diamond interfaces for GaN-on-diamond devices. ACS Appl. Mater. Interfaces 12, 8376–8384 (2020).


    Google Scholar
     

  • Cheng, Z. et al. Tunable thermal energy transport across diamond membranes and diamond–Si interfaces by nanoscale graphoepitaxy. ACS Appl. Mater. Interfaces 11, 18517–18527 (2019).

    ADS 

    Google Scholar
     

  • Cahill, D. G. et al. Nanoscale thermal transport. II. 2003–2012. Appl. Phys. Rev. 1, 011305 (2014).

    ADS 

    Google Scholar
     

  • Giri, A. & Hopkins, P. E. A review of experimental and computational advances in thermal boundary conductance and nanoscale thermal transport across solid interfaces. Adv. Funct. Mater. 30, 1903857 (2020).


    Google Scholar
     

  • Chen, J., Xu, X., Zhou, J. & Li, B. Interfacial thermal resistance: past, present, and future. Rev. Mod. Phys. 94, 025002 (2022).

    ADS 
    MathSciNet 

    Google Scholar
     

  • Wilson, R. B. & Cahill, D. G. Experimental validation of the interfacial form of the Wiedemann–Franz law. Phys. Rev. Lett. 108, 255901 (2012).

    ADS 

    Google Scholar
     

  • Cheng, Z. et al. Thermal conductance across harmonic-matched epitaxial Al–sapphire heterointerfaces. Commun. Phys. 3, 115 (2020).


    Google Scholar
     

  • Gaskins, J. T. et al. Thermal boundary conductance across heteroepitaxial ZnO/GaN interfaces: assessment of the phonon gas model. Nano. Lett. 18, 7469–7477 (2018).

    ADS 

    Google Scholar
     

  • Norris, P. M. & Hopkins, P. E. Examining interfacial diffuse phonon scattering through transient thermoreflectance measurements of thermal boundary conductance. J. Heat. Transf. 131, 043207 (2009).


    Google Scholar
     

  • Wilson, R. B., Apgar, B. A., Hsieh, W.-P., Martin, L. W. & Cahill, D. G. Thermal conductance of strongly bonded metal–oxide interfaces. Phys. Rev. B 91, 115414 (2015).

    ADS 

    Google Scholar
     

  • Angeles, F. et al. Interfacial thermal transport in spin caloritronic material systems. Phys. Rev. Mater. 5, 114403 (2021).


    Google Scholar
     

  • Hopkins, P. E. et al. Manipulating thermal conductance at metal–graphene contacts via chemical functionalization. Nano. Lett. 12, 590–595 (2012).

    ADS 

    Google Scholar
     

  • Vaziri, S. et al. Ultrahigh thermal isolation across heterogeneously layered two-dimensional materials. Sci. Adv. 5, eaax1325 (2019).

    ADS 

    Google Scholar
     

  • Lyeo, H.-K. & Cahill, D. G. Thermal conductance of interfaces between highly dissimilar materials. Phys. Rev. B 73, 144301 (2006).

    ADS 

    Google Scholar
     

  • Hohensee, G. T., Fellinger, M. R., Trinkle, D. R. & Cahill, D. G. Thermal transport across high-pressure semiconductor-metal transition in Si and Si0.991Ge0.009. Phys. Rev. B 91, 205104 (2015).

    ADS 

    Google Scholar
     

  • Dalton, D. A., Hsieh, W.-P., Hohensee, G. T., Cahill, D. G. & Goncharov, A. F. Effect of mass disorder on the lattice thermal conductivity of MgO periclase under pressure. Sci. Rep. 3, 2400 (2013).


    Google Scholar
     

  • Hsieh, W.-P. et al. Testing the minimum thermal conductivity model for amorphous polymers using high pressure. Phys. Rev. B 83, 174205 (2011).

    ADS 

    Google Scholar
     

  • Hohensee, G. T., Wilson, R. B. & Cahill, D. G. Thermal conductance of metal–diamond interfaces at high pressure. Nat. Commun. 6, 6578 (2015).

    ADS 

    Google Scholar
     

  • Hsieh, W.-P., Lyons, A. S., Pop, E., Keblinski, P. & Cahill, D. G. Pressure tuning of the thermal conductance of weak interfaces. Phys. Rev. B 84, 184107 (2011).

    ADS 

    Google Scholar
     

  • Hsieh, W.-P., Chen, B., Li, J., Keblinski, P. & Cahill, D. G. Pressure tuning of the thermal conductivity of the layered muscovite crystal. Phys. Rev. B 80, 180302 (2009).

    ADS 

    Google Scholar
     

  • Sääskilahti, K., Oksanen, J., Tulkki, J. & Volz, S. Role of anharmonic phonon scattering in the spectrally decomposed thermal conductance at planar interfaces. Phys. Rev. B 90, 134312 (2014).

    ADS 

    Google Scholar
     

  • Lu, Z., Chaka, A. M. & Sushko, P. V. Thermal conductance enhanced via inelastic phonon transport by atomic vacancies at Cu/Si interfaces. Phys. Rev. B 102, 075449 (2020).

    ADS 

    Google Scholar
     

  • Stevens, R. J., Zhigilei, L. V. & Norris, P. M. Effects of temperature and disorder on thermal boundary conductance at solid–solid interfaces: nonequilibrium molecular dynamics simulations. Int. J. Heat. Mass. Transf. 50, 3977–3989 (2007).

    ADS 

    Google Scholar
     

  • Dai, J. & Tian, Z. Rigorous formalism of anharmonic atomistic Green’s function for three-dimensional interfaces. Phys. Rev. B 101, 041301 (2020).

    ADS 

    Google Scholar
     

  • Guo, Y. et al. Anharmonic phonon–phonon scattering at the interface between two solids by nonequilibrium Green’s function formalism. Phys. Rev. B 103, 174306 (2021).

    ADS 

    Google Scholar
     

  • Sadasivam, S. et al. Thermal transport across metal silicide-silicon interfaces: first-principles calculations and Green’s function transport simulations. Phys. Rev. B 95, 085310 (2017).

    ADS 

    Google Scholar
     

  • Majumdar, A. & Reddy, P. Role of electron–phonon coupling in thermal conductance of metal–nonmetal interfaces. Appl. Phys. Lett. 84, 4768–4770 (2004).

    ADS 

    Google Scholar
     

  • Sergeev, A. V. Electronic Kapitza conductance due to inelastic electron-boundary scattering. Phys. Rev. B 58, R10199–R10202 (1998).

    ADS 

    Google Scholar
     

  • Sergeev, A. Inelastic electron–boundary scattering in thin films. Phys. B Condens. Matter 263–264, 217–219 (1999).

    ADS 

    Google Scholar
     

  • Mahan, G. D. Kapitza thermal resistance between a metal and a nonmetal. Phys. Rev. B 79, 075408 (2009).

    ADS 

    Google Scholar
     

  • Hopkins, P. E., Kassebaum, J. L. & Norris, P. M. Effects of electron scattering at metal–nonmetal interfaces on electron–phonon equilibration in gold films. J. Appl. Phys. 105, 023710 (2009).

    ADS 

    Google Scholar
     

  • Wang, Y., Ruan, X. & Roy, A. K. Two-temperature nonequilibrium molecular dynamics simulation of thermal transport across metal–nonmetal interfaces. Phys. Rev. B 85, 205311 (2012).

    ADS 

    Google Scholar
     

  • P. Rudolph, ed. Handbook of Crystal Growth, Bulk Crystal Growth Vol. II (Elsevier, 2015).

  • Li, S. et al. High thermal conductivity in cubic boron arsenide crystals. Science 361, 579–581 (2018).

    ADS 

    Google Scholar
     

  • Hou, S. et al. Strong temperature dependence of thermal conductivity in high-purity cubic boron arsenide. Phys. Rev. B 111, 23520 (2025).


    Google Scholar
     

  • Hou, S. et al. Thermal conductivity of BAs under pressure. Adv. Electron. Mater. 8, 2200017 (2022).


    Google Scholar
     

  • Chen, K. et al. Ultrahigh thermal conductivity in isotope-enriched cubic boron nitride. Science 367, 555–559 (2020).

    ADS 

    Google Scholar
     

  • Kang, J. S., Wu, H. & Hu, Y. Thermal properties and phonon spectral characterization of synthetic boron phosphide for high thermal conductivity applications. Nano Lett. 17, 7507–7514 (2017).

    ADS 

    Google Scholar
     

  • Zheng, Q. et al. High thermal conductivity in isotopically enriched cubic boron phosphide. Adv. Funct. Mater. 28, 1805116 (2018).


    Google Scholar
     

  • Lv, B. et al. Experimental study of the proposed super-thermal-conductor: BAs. Appl. Phys. Lett. 106, 074105 (2015).

    ADS 

    Google Scholar
     

  • Feng, T., Lindsay, L. & Ruan, X. Four-phonon scattering significantly reduces intrinsic thermal conductivity of solids. Phys. Rev. B 96, 161201 (2017).

    ADS 

    Google Scholar
     

  • Lindsay, L., Broido, D. A. & Reinecke, T. L. First-principles determination of ultrahigh thermal conductivity of boron arsenide: a competitor for diamond? Phys. Rev. Lett. 111, 025901 (2013).

    ADS 

    Google Scholar
     

  • Broido, D. A., Lindsay, L. & Reinecke, T. L. Ab initio study of the unusual thermal transport properties of boron arsenide and related materials. Phys. Rev. B 88, 214303 (2013).

    ADS 

    Google Scholar
     

  • Ravichandran, N. K. & Broido, D. Non-monotonic pressure dependence of the thermal conductivity of boron arsenide. Nat. Commun. 10, 827 (2019).


    Google Scholar
     

  • Mion, C., Muth, J. F., Preble, E. A. & Hanser, D. Thermal conductivity, dislocation density and GaN device design. Superlatt. Microstruct. 40, 338–342 (2006).

    ADS 

    Google Scholar
     

  • Zou, J., Kotchetkov, D., Balandin, A. A., Florescu, D. I. & Pollak, F. H. Thermal conductivity of GaN films: effects of impurities and dislocations. J. Appl. Phys. 92, 2534–2539 (2002).

    ADS 

    Google Scholar
     

  • Beechem, T. E. et al. Size dictated thermal conductivity of GaN. J. Appl. Phys. 120, 095104 (2016).

    ADS 

    Google Scholar
     

  • Koh, Y. R. et al. Bulk-like intrinsic phonon thermal conductivity of micrometer-thick AlN films. ACS Appl. Mater. Interfaces 12, 29443–29450 (2020).


    Google Scholar
     

  • Sood, A. et al. Anisotropic and inhomogeneous thermal conduction in suspended thin-film polycrystalline diamond. J. Appl. Phys. 119, 175103 (2016).

    ADS 

    Google Scholar
     

  • Jiang, P., Lindsay, L., Huang, X. & Koh, Y. K. Interfacial phonon scattering and transmission loss in >1 μm thick silicon-on-insulator thin films. Phys. Rev. B 97, 195308 (2018).

    ADS 

    Google Scholar
     

  • Sun, B. et al. Dislocation-induced thermal transport anisotropy in single-crystal group-III nitride films. Nat. Mater. 18, 136–140 (2019).

    ADS 

    Google Scholar
     

  • Cahill, D. G., Watson, S. K. & Pohl, R. O. Lower limit to the thermal conductivity of disordered crystals. Phys. Rev. B 46, 6131–6140 (1992).

    ADS 

    Google Scholar
     

  • Duda, J. C., Hopkins, P. E., Shen, Y. & Gupta, M. C. Thermal transport in organic semiconducting polymers. Appl. Phys. Lett. 102, 251912 (2013).

    ADS 

    Google Scholar
     

  • Giri, A. et al. Molecular tail chemistry controls thermal transport in fullerene films. Phys. Rev. Mater. 4, 65404 (2020).


    Google Scholar
     

  • Chiritescu, C. et al. Ultralow thermal conductivity in disordered, layered WSe2 crystals. Science 315, 351–353 (2007). This work presents an experimental realization of the lowest thermal conductivity fully dense solid at room temperature with TDTR.

    ADS 

    Google Scholar
     

  • Hadland, E. C. et al. Ultralow thermal conductivity of turbostratically disordered MoSe2 ultra-thin films and implications for heterostructures. Nanotechnology 30, 285401 (2019).


    Google Scholar
     

  • Kim, S. E. et al. Extremely anisotropic van der Waals thermal conductors. Nature 597, 660–665 (2021).

    ADS 

    Google Scholar
     

  • Li, D., Schleife, A., Cahill, D. G., Mitchson, G. & Johnson, D. C. Ultralow shear modulus of incommensurate [SnSe]n[MoSe2]n layers synthesized by the method of modulated elemental reactants. Phys. Rev. Mater. 3, 043607 (2019).


    Google Scholar
     

  • Hadland, E. et al. Synthesis, characterization, and ultralow thermal conductivity of a lattice-mismatched SnSe2(MoSe2)1.32 heterostructure. Chem. Mater. 31, 5699–5705 (2019).


    Google Scholar
     

  • Gunning, N. S., Feser, J., Beekman, M., Cahill, D. G. & Johnson, D. C. Synthesis and thermal properties of solid-state structural isomers: ordered intergrowths of SnSe and MoSe2. J. Am. Chem. Soc. 137, 8803–8809 (2015).


    Google Scholar
     

  • Dai, H. & Wang, R. Methods for measuring thermal conductivity of two-dimensional materials: a review. Nanomaterials 12, 589 (2022).


    Google Scholar
     

  • Dong, Y., Wu, Z.-S., Ren, W., Cheng, H.-M. & Bao, X. Graphene: a promising 2D material for electrochemical energy storage. Sci. Bull. 62, 724–740 (2017).


    Google Scholar
     

  • Munteanu, R.-E., Moreno, P. S., Bramini, M. & Gáspár, S. 2D materials in electrochemical sensors for in vitro or in vivo use. Anal. Bioanal. Chem. 413, 701–725 (2021).


    Google Scholar
     

  • Wang, X. et al. Recent advances in the functional 2D photonic and optoelectronic devices. Adv. Opt. Mater. 7, 1801274 (2019).


    Google Scholar
     

  • Jiang, P., Qian, X., Gu, X. & Yang, R. Probing anisotropic thermal conductivity of transition metal dichalcogenides MX2 (M = Mo, W and X = S, Se) using time-domain thermoreflectance. Adv. Mater. 29, 1701068 (2017).


    Google Scholar
     

  • Xu, K. et al. In-plane thermal diffusivity determination using beam-offset frequency-domain thermoreflectance with a one-dimensional optical heat source. Int. J. Heat. Mass. Transf. 214, 124376 (2023).


    Google Scholar
     

  • Gu, X. & Yang, R. Phonon transport in single-layer transition metal dichalcogenides: a first-principles study. Appl. Phys. Lett. 105, 131903 (2014).

    ADS 

    Google Scholar
     

  • Zhu, G. et al. Tuning thermal conductivity in molybdenum disulfide by electrochemical intercalation. Nat. Commun. 7, 13211 (2016).

    ADS 

    Google Scholar
     

  • Jiang, P., Qian, X., Li, X. & Yang, R. Three-dimensional anisotropic thermal conductivity tensor of single crystalline β-Ga2O3. Appl. Phys. Lett. 113, 232105 (2018).

    ADS 

    Google Scholar
     

  • Sood, A. et al. Direct visualization of thermal conductivity suppression due to enhanced phonon scattering near individual grain boundaries. Nano. Lett. 18, 3466–3472 (2018).

    ADS 

    Google Scholar
     

  • Grimm, D. et al. Thermal conductivity of mechanically joined semiconducting/metal nanomembrane superlattices. Nano. Lett. 14, 2387–2393 (2014).

    ADS 

    Google Scholar
     

  • Cheng, Z. et al. Probing local thermal conductivity variations in CVD diamond with large grains by time-domain thermoreflectance. In Proc. Int. Heat Transf. Conf. Vol. 16 8694–8701 (Begellhouse, 2018).

  • Sood, A. et al. An electrochemical thermal transistor. Nat. Commun. 9, 4510 (2018).

    ADS 

    Google Scholar
     

  • Brown, D. B. et al. Spatial mapping of thermal boundary conductance at metal–molybdenum diselenide interfaces. ACS Appl. Mater. Interfaces 11, 14418–14426 (2019).


    Google Scholar
     

  • Cheaito, R. et al. Thermal conductivity measurements on suspended diamond membranes using picosecond and femtosecond time-domain thermoreflectance. In Proc. IEEE Intersoc. Conf. Therm. Thermomech. Phenom. Electron. Syst. (ITherm) 706–710 (IEEE, 2017).

  • Zheng, X., Cahill, D., Krasnochtchekov, P., Averback, R. & Zhao, J. High-throughput thermal conductivity measurements of nickel solid solutions and the applicability of the Wiedemann–Franz law. Acta. Mater. 55, 5177–5185 (2007).

    ADS 

    Google Scholar
     

  • Zhao, J.-C., Zheng, X. & Cahill, D. G. Thermal conductivity mapping of the Ni–Al system and the β-NiAl phase in the Ni–Al–Cr system. Scr. Mater. 66, 935–938 (2012).


    Google Scholar
     

  • Germain, T., Chowdhury, T. A., Carter, J. & Putnam, S. A. Measuring heat transfer coefficients for microchannel jet impingement using time-domain thermoreflectance. In Proc. IEEE Intersoc. Conf. Therm. Thermomech. Phenom. Electron. Syst. (ITherm) 449–454 (IEEE, 2018).

  • Mehrvand, M. & Putnam, S. A. Probing the local heat transfer coefficient of |water-cooled microchannels using time-domain thermoreflectance. J. Heat. Transf. 139, 112403 (2017).


    Google Scholar
     

  • Mehrvand, M. & Putnam, S. A. Transient and local two-phase heat transport at macro-scales to nano-scales. Commun. Phys. 1, 21 (2018).


    Google Scholar
     

  • Xie, X., Diao, Z. & Cahill, D. G. Microscale, bendable thermoreflectance sensor for local measurements of the thermal effusivity of biological fluids and tissues. Rev. Sci. Instrum. 91, 044903 (2020).

    ADS 

    Google Scholar
     

  • Tian, Z., Marconnet, A. & Chen, G. Enhancing solid–liquid interface thermal transport using self-assembled monolayers. Appl. Phys. Lett. 106, 211602 (2015).

    ADS 

    Google Scholar
     

  • Ge, Z., Cahill, D. G. & Braun, P. V. Thermal conductance of hydrophilic and hydrophobic interfaces. Phys. Rev. Lett. 96, 186101 (2006). This work measures the thermal boundary conductance across solid–liquid interfaces with TDTR.

    ADS 

    Google Scholar
     

  • Hsieh, W. P. & Deschamps, F. Thermal conductivity of H2O–CH3OH mixtures at high pressures: implications for the dynamics of icy super-Earths outer shells. J. Geophys. Res. Planets 120, 1697–1707 (2015).

    ADS 

    Google Scholar
     

  • Yong Park, J., Gardner, A., King, W. P. & Cahill, D. G. Droplet impingement and vapor layer formation on hot hydrophobic surfaces. J. Heat. Transf. 136, 092902 (2014).


    Google Scholar
     

  • Yong Park, J., Min, C.-K., Granick, S. & Cahill, D. G. Residence time and heat transfer when water droplets hit a scalding surface. J. Heat. Transf. 134, 101503 (2012).


    Google Scholar
     

  • Shin, J. et al. Thermally functional liquid crystal networks by magnetic field driven molecular orientation. ACS Macro. Lett. 5, 955–960 (2016).


    Google Scholar
     

  • Ueji, K. et al. In situ time-domain thermoreflectance measurements using Au as the transducer during electrolyte gating. Appl. Phys. Lett. 117, 133104 (2020).

    ADS 

    Google Scholar
     

  • Zhang, D.-L. et al. High-frequency magnetoacoustic resonance through strain–spin coupling in perpendicular magnetic multilayers. Sci. Adv. 6, eabb4607 (2020).

    ADS 

    Google Scholar
     

  • Chen, B., Hsieh, W. P., Cahill, D. G., Trinkle, D. R. & Li, J. Thermal conductivity of compressed H2O to 22 GPa: a test of the Leibfried–Schlömann equation. Phys. Rev. B 83, 132301 (2011).

    ADS 

    Google Scholar
     

  • Ortiz, V. H. et al. Thermal conductivity of irradiated tetragonal lithium aluminate. J. Nucl. Mater. 606, 155585 (2025).


    Google Scholar
     

  • Cheaito, R., Gorham, C. S., Misra, A., Hattar, K. & Hopkins, P. E. Thermal conductivity measurements via time-domain thermoreflectance for the characterization of radiation induced damage. J. Mater. Res. 30, 1403–1412 (2015).

    ADS 

    Google Scholar
     

  • Alaie, S. et al. Reduction and increase in thermal conductivity of Si irradiated with Ga+ via focused ion beam. ACS Appl. Mater. Interfaces 10, 37679–37684 (2018).


    Google Scholar
     

  • Pfeifer, T. W. et al. Measuring sub-surface spatially varying thermal conductivity of silicon implanted with krypton. J. Appl. Phys. 132, 075112 (2022). This work demonstrates resolving the thermal conductivity as a function of depth of irradiated silicon with TDTR.


    Google Scholar
     

  • Scott, E. A. et al. Orders of magnitude reduction in the thermal conductivity of polycrystalline diamond through carbon, nitrogen, and oxygen ion implantation. Carbon 157, 97–105 (2020).


    Google Scholar
     

  • Scott, E. A. et al. Reductions in the thermal conductivity of irradiated silicon governed by displacement damage. Phys. Rev. B 104, 134306 (2021).

    ADS 

    Google Scholar
     

  • Scott, E. A. et al. Phonon scattering effects from point and extended defects on thermal conductivity studied via ion irradiation of crystals with self-impurities. Phys. Rev. Mater. 2, 095001 (2018).

    ADS 

    Google Scholar
     

  • Scott, E. A. et al. Thermal conductivity enhancement in ion-irradiated hydrogenated amorphous carbon films. Nano Lett. 21, 3935–3940 (2021).

    ADS 

    Google Scholar
     

  • Pfeifer, T. W. et al. Ion irradiation induced crystalline disorder accelerates interfacial phonon conversion and reduces thermal boundary resistance. Phys. Rev. B 109, 165421 (2024).

    ADS 

    Google Scholar
     

  • Gorham, C. S. et al. Ion irradiation of the native oxide/silicon surface increases the thermal boundary conductance across aluminum/silicon interfaces. Phys. Rev. B 90, 024301 (2014).

    ADS 

    Google Scholar
     

  • Hopkins, P. E. et al. Influence of anisotropy on thermal boundary conductance at solid interfaces. Phys. Rev. B 84, 125408 (2011).

    ADS 

    Google Scholar
     

  • Hopkins, P. E. et al. Reduction in thermal boundary conductance due to proton implantation in silicon and sapphire. Appl. Phys. Lett. 98, 231901 (2011).

    ADS 

    Google Scholar
     

  • Zheng, X. & Eng, B. High-throughput Measurements of Thermal Conductivity and the Coefficient of Thermal Expansion (Univ. of Illinois at Urbana-Champaign, 2008).

  • Rost, C. M. et al. Hafnium nitride films for thermoreflectance transducers at high temperatures: potential based on heating from laser absorption. Appl. Phys. Lett. 111, 151902 (2017).

    ADS 

    Google Scholar
     

  • Wilson, R. B. & Cahill, D. G. Anisotropic failure of Fourier theory in time-domain thermoreflectance experiments. Nat. Commun. 5, 5075 (2014). This work presents a set of comprehensive measurements, analyses and discussion ofmean free path spectroscopyeffects in TDTR measurements.

    ADS 

    Google Scholar
     

  • Minnich, A. J. et al. Thermal conductivity spectroscopy technique to measure phonon mean free paths. Phys. Rev. Lett. 107, 095901 (2011).

    ADS 

    Google Scholar
     

  • Koh, Y. K. & Cahill, D. G. Frequency dependence of the thermal conductivity of semiconductor alloys. Phys. Rev. B 76, 075207 (2007).

    ADS 

    Google Scholar
     

  • Regner, K. T. et al. Broadband phonon mean free path contributions to thermal conductivity measured using frequency domain thermoreflectance. Nat. Commun. 4, 1640 (2013).

    ADS 

    Google Scholar
     

  • Wilson, R. B. & Cahill, D. G. Limits to Fourier theory in high thermal conductivity single crystals. Appl. Phys. Lett. 107, 203112 (2015).

    ADS 

    Google Scholar
     

  • Vermeersch, B., Mohammed, A. M. S., Pernot, G., Koh, Y. R. & Shakouri, A. Superdiffusive heat conduction in semiconductor alloys. II. Truncated Lévy formalism for experimental analysis. Phys. Rev. B 91, 085203 (2015).

    ADS 

    Google Scholar
     

  • Vermeersch, B., Carrete, J., Mingo, N. & Shakouri, A. Superdiffusive heat conduction in semiconductor alloys. I. Theoretical foundations. Phys. Rev. B 91, 085202 (2015).

    ADS 

    Google Scholar
     

  • Li, X., Han, J. & Lee, S. Thermal resistance from non-equilibrium phonons at Si–Ge interface. Mater. Today Phys. 34, 101063 (2023).


    Google Scholar
     

  • Han, J. & Lee, S. Thermal resistance across Si–SiGe alloy interface from phonon distribution mismatch. Appl. Phys. Lett. 124, 142201 (2024).

    ADS 

    Google Scholar
     

  • Han, J. & Lee, S. Nonequilibrium thermal resistance of interfaces between III–V compounds. Phys. Rev. Mater. 8, 014604 (2024).


    Google Scholar
     

  • Hua, C., Chen, X., Ravichandran, N. K. & Minnich, A. J. Experimental metrology to obtain thermal phonon transmission coefficients at solid interfaces. Phys. Rev. B 95, 205423 (2017).

    ADS 

    Google Scholar
     

  • Hoque, M. S. B. et al. High in-plane thermal conductivity of aluminum nitride thin films. ACS Nano 15, 9588–9599 (2021).


    Google Scholar
     

  • Tadjer, M. J. et al. Effect of GaN/AlGaN buffer thickness on the electrothermal performance of AlGaN/GaN high electron mobility transistors on engineered substrates. Phys. Status Solidi A 220, 2200828 (2023).

    ADS 

    Google Scholar
     

  • Hoque, M. S. B. et al. Connection length controlled sound speed and thermal conductivity of hybrid metalcone films. Nano Lett. 25, 2594–2599 (2025).


    Google Scholar
     

  • Aller, H. T. et al. Low thermal resistance of diamond–AlGaN interfaces achieved using carbide interlayers. Adv. Mater. Interfaces 12, 2400575 (2025).


    Google Scholar
     

  • Pfeifer, T. W. et al. Limitations and advances in optical thermometry: nanoscale resistances, ultrahigh thermal conductivity, and ultrahigh temperatures. Annu. Rev. Mater. Res. 55, 080423-010435 (2025).


    Google Scholar
     

  • Hopkins, P. E. et al. Effect of dislocation density on thermal boundary conductance across GaSb/GaAs interfaces. Appl. Phys. Lett. 98, 161913 (2011).

    ADS 

    Google Scholar
     

  • Chen, G. Nonlocal and nonequilibrium heat conduction in the vicinity of nanoparticles. J. Heat. Transf. 118, 539 (1996).


    Google Scholar
     

  • Braun, J. L., Szwejkowski, C. J., Giri, A. & Hopkins, P. E. On the steady-state temperature rise during laser heating of multilayer thin films in optical pump–probe techniques. J. Heat. Transf. 140, 052801 (2018).


    Google Scholar
     

  • Scott, E. A. et al. Probing thermal conductivity of subsurface, amorphous layers in irradiated diamond. J. Appl. Phys. 129, 055307 (2021).

    ADS 

    Google Scholar
     

  • Bin Hoque, Md. S. et al. Thermal conductivity measurements of sub-surface buried substrates by steady-state thermoreflectance. Rev. Sci. Instrum. 92, 64906 (2021).


    Google Scholar
     

  • Salnick, A. & Opsal, J. Dynamics of the plasma and thermal waves in surface-modified semiconductors. Rev. Sci. Instrum. 74, 545–549 (2003).

    ADS 

    Google Scholar
     

  • Schmidt, A. J., Cheaito, R. & Chiesa, M. A frequency-domain thermoreflectance method for the characterization of thermal properties. Rev. Sci. Instrum. 80, 94901 (2009). This work introduces the development of FDTR.


    Google Scholar
     

  • Schmidt, A. J., Cheaito, R. & Chiesa, M. Characterization of thin metals films via frequency-domain thermoreflectance. J. Appl. Phys. 107, 24908 (2010).


    Google Scholar
     

  • Regner, K. T., Majumdar, S. & Malen, J. A. Instrumentation of broadband frequency domain thermoreflectance for measuring thermal conductivity accumulation functions. Rev. Sci. Instrum. 84, 64901 (2013).


    Google Scholar
     

  • Ziade, E. Wide bandwidth frequency-domain thermoreflectance: volumetric heat capacity, anisotropic thermal conductivity, and thickness measurements. Rev. Sci. Instrum. 91, 124901 (2020).

    ADS 

    Google Scholar
     

  • Ziade, E. et al. Thickness dependent thermal conductivity of gallium nitride. Appl. Phys. Lett. 110, 31903 (2017).


    Google Scholar
     

  • Scott, E. A. et al. Thermal conductivity of (Ge2Sb2Te5)1–xCx phase change films. J. Appl. Phys. 128, 155106 (2020).

    ADS 

    Google Scholar
     

  • Kirsch, D. J. et al. An instrumentation guide to measuring thermal conductivity using frequency domain thermoreflectance (FDTR). Rev. Sci. Instrum. 95, 103006 (2024).


    Google Scholar
     

  • Xiang, Z., Pang, Y., Qian, X. & Yang, R. Machine learning reconstruction of depth-dependent thermal conductivity profile from pump–probe thermoreflectance signals. Appl. Phys. Lett. 122, 142201 (2023). This work uses machine learning to analyse TDTR data.

    ADS 

    Google Scholar
     

  • Shen, W., Vaca, D. & Kumar, S. Reconsidering uncertainty from frequency domain thermoreflectance measurement and novel data analysis by deep learning. Nanoscale Microscale Thermophys. Eng. 24, 138–149 (2020).

    ADS 

    Google Scholar
     

  • Hodges, W., Jarzembski, A., McDonald, A., Ziade, E. & Pickrell, G. W. Sensing depths in frequency domain thermoreflectance. J. Appl. Phys. 131, 245103 (2022).

    ADS 

    Google Scholar
     

  • Delmas, W. et al. Thermal transport and mechanical stress mapping of a compression bonded GaN/diamond interface for vertical power devices. ACS Appl. Mater. Interfaces 16, 11003–11012 (2024).


    Google Scholar
     

  • Zandavi, S. H., Schmidt, A. & Brun, X. Assessing thermal resistance in fusion bond layers of 3D heterogeneous electronics packaging. J. Appl. Phys. 136, 155303 (2024).


    Google Scholar
     

  • Poopakdee, N., Abdallah, Z., Pomeroy, J. W. & Kuball, M. In situ thermoreflectance characterization of thermal resistance in multilayer electronics packaging. ACS Appl. Electron. Mater. 4, 1558–1566 (2022).


    Google Scholar
     

  • Wang, L., Cheaito, R., Braun, J. L., Giri, A. & Hopkins, P. E. Thermal conductivity measurements of non-metals via combined time- and frequency-domain thermoreflectance without a metal film transducer. Rev. Sci. Instrum. 87, 094902 (2016). This study extends TDTR to probe thermal properties without a metal film transducer (such astransducerlessTDTR).

    ADS 

    Google Scholar
     

  • Hutchins, W. et al. Ultrafast evanescent heat transfer across solid interfaces via hyperbolic phonon polaritons in hexagonal boron nitride. Nat. Mater. 24, 698–706 (2025).


    Google Scholar
     

  • Folland, T. G., Nordin, L., Wasserman, D. & Caldwell, J. D. Probing polaritons in the mid- to far-infrared. J. Appl. Phys. 125, 191102 (2019).

    ADS 

    Google Scholar
     

  • Hutchins, W. D., Zare, S., Hirt, D., Golightly, E. & Hopkins, P. E. Infrared phonon thermoreflectance in polar dielectrics. Preprint at https://arxiv.org/abs/2504.05675 (2025).

  • Majumdar, A. Scanning thermal microscopy. Annu. Rev. Mater. Sci. 29, 505–585 (1999).

    ADS 

    Google Scholar
     

  • Zhang, Y. et al. A review on principles and applications of scanning thermal microscopy (SThM). Adv. Funct. Mater. 30, 1900892 (2020).


    Google Scholar
     

  • Siemens, M. E. et al. Quasi-ballistic thermal transport from nanoscale interfaces observed using ultrafast coherent soft X-ray beams. Nat. Mater. 9, 26–30 (2010).

    ADS 

    Google Scholar
     

  • Hu, Y., Zeng, L., Minnich, A. J., Dresselhaus, M. S. & Chen, G. Spectral mapping of thermal conductivity through nanoscale ballistic transport. Nat. Nanotechnol. 10, 701–706 (2015).

    ADS 

    Google Scholar
     

  • Kwon, H., Perez, C., Park, W., Asheghi, M. & Goodson, K. E. Thermal characterization of metal–oxide interfaces using time-domain thermoreflectance with nanograting transducers. ACS Appl. Mater. Interfaces 13, 58059–58065 (2021).


    Google Scholar
     

  • Höppener, C. et al. Tip-enhanced Raman scattering. Nat. Rev. Methods Primers 4, 47 (2024).


    Google Scholar
     

  • Caldwell, J. D. et al. Low-loss, infrared and terahertz nanophotonics using surface phonon polaritons. Nanophotonics 4, 44–68 (2015).


    Google Scholar
     

  • Eichfeld, D. A., Maniyara, R. A., Robinson, J. A., Foley, B. M. & Ramos-Alvarado, B. A novel approach to measuring local mechanical properties via photothermal excitation of an atomic force microscope probe using an optical pump–probe inspired design. AIP Adv. 13, 105035 (2023).

    ADS 

    Google Scholar
     

  • Zhang, Y., Zhu, Q. & Borca-Tasciuc, T. Thermal conductivity measurements of thin films by non-contact scanning thermal microscopy under ambient conditions. Nanoscale Adv. 3, 692–702 (2021).

    ADS 

    Google Scholar
     

  • Foley, B. M., Gaskins, J. T. & Hopkins, P. E. Fiber-optic based thermal reflectance material property measurement system and related methods. US Patent 10928317 B2 (2021).

  • Malen, J. A. et al. Optical measurement of thermal conductivity using fiber aligned frequency domain thermoreflectance. J. Heat. Transf. 133, 081601 (2011).


    Google Scholar
     

  • Dennett, C. A., Buller, D. L., Hattar, K. & Short, M. P. Real-time thermomechanical property monitoring during ion beam irradiation using in situ transient grating spectroscopy. Nucl. Instrum. Methods Phys. Res. B 440, 126–138 (2019).

    ADS 

    Google Scholar
     

  • Reza, A. et al. Non-contact, non-destructive mapping of thermal diffusivity and surface acoustic wave speed using transient grating spectroscopy. Rev. Sci. Instrum. 91, 054902 (2020).

    ADS 

    Google Scholar