Researchers from the City University of New York, Yale University, Caltech, Kansas State University, and international collaborators have discovered a new way of generating phonon-polaritons, a unique type of electromagnetic wave that occurs when light interacts with vibrations in a material’s crystal lattice structure. This advance could pave the way for cheaper, smaller long-wave infrared light sources and more efficient device cooling. The researchers made that discovery by using a thin layer of graphene sandwiched between two hexagonal boron nitride slabs. Until now, exciting and detecting phonon-polariton waves has been expensive – typically involving costly mid-infrared or terahertz lasers and near-field scanning probes – but in this study, the researchers used a cheaper alternative: an electrical current generated by applying an electric field to the graphene.
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