Trillions of ghostly particles called neutrinos stream through our bodies every second, slipping past atoms without a trace. Smaller than electrons and lighter than photons, they\u2019re the most abundant particles with mass in the universe \u2014 yet their properties remain some of physics\u2019 biggest mysteries.<\/p>\n
Now, MIT physicists have proposed a bold new way to probe these elusive particles: by building the world\u2019s first neutrino laser. Unlike massive reactors or particle accelerators, this setup could fit on a tabletop.<\/p>\n
In a study, the team describes how cooling a gas of radioactive atoms to temperatures colder than deep space could synchronize their radioactive decay. In this quantum state, the atoms would emit a supercharged burst of neutrinos, similar to how photons are amplified in a conventional laser beam.<\/p>\n
\u201cIn our concept for a neutrino laser, the neutrinos would be emitted at a much faster rate than they normally would, sort of like a laser emits photons very fast,\u201d says co-author Ben Jones, associate professor of physics at the University of Texas at Arlington.<\/p>\n
Radioactive atoms in sync<\/p>\n
Normally, radioactive atoms decay slowly. For instance, rubidium-83 has a half-life of 82 days, meaning half the atoms would release neutrinos over nearly three months.<\/p>\n
But the researchers calculated that if a million rubidium-83 atoms were cooled into a Bose-Einstein condensate, a quantum state where atoms behave as one, the synchronized decay could occur within minutes, producing a rapid, coherent stream of neutrinos.<\/p>\n
\u201cThis is a novel way to accelerate radioactive decay and the production of neutrinos, which to my knowledge, has never been done,\u201d says MIT physics professor and co-author Joseph Formaggio.<\/p>\n
The idea borrows from a well-known optical effect called superradiance, where atoms emit light in sync, amplifying the emission. Applying the same physics to radioactive atoms, the team found, could lead to an amplified burst of neutrinos.<\/p>\n
Potential beyond physics<\/p>\n
If successful, the neutrino laser could open surprising possibilities. One is communication: neutrinos barely interact<\/a> with matter, meaning a beam could pass straight through Earth, reaching underground stations or even deep-space habitats without interference.<\/p>\n Another is medicine. Alongside neutrinos, radioactive decay produces isotopes that could enhance cancer diagnostics and imaging techniques.<\/p>\n \u201cIt should be enough to take this radioactive material, vaporize it, trap it with lasers, cool it down, and then turn it into a Bose-Einstein condensate,\u201d Jones says. \u201cThen it should start doing this superradiance spontaneously.\u201d<\/p>\n Building such a device won\u2019t be simple. Creating a condensate from radioactive atoms has never been achieved, and the experiment would require extreme precision and strict safety measures. Still, the researchers are optimistic that a small-scale demonstration is within reach.<\/p>\n \u201cIf it turns out that we can show it in the lab, then people can think about: Can we use this as a neutrino<\/a> detector? Or a new form of communication?\u201d Formaggio says. \u201cThat\u2019s when the fun really starts.\u201d<\/p>\n