Ultraconfined terahertz phonon polaritons in hafnium dichalcogenides
Li, N. et al. Direct observation of highly confined phonon polaritons in suspended monolayer hexagonal boron nitride. Nat.…
A lithography-free approach to polaritonic Luneburg lenses
Gradient indices from dielectric environment engineering The propagation of polaritons is significantly influenced by the surrounding dielectric environment,…
Microscopic theory of polariton group velocity renormalization
Model system We use the Generalized Holstein-Tavis-Cummings (GHTC) Hamiltonian23,24,25,26 to describe N excitons interacting with \({{{\mathcal{M}}}}\) cavity modes,…
X-ray parametric down-conversion reveals EUV-polariton
Experimental setup We performed the experiment at the large solid-angle spectrometer of beamline ID20 at ESRF26. The setup’s…