Green's functions of the Boltzmann transport equation with the full scattering matrix for phonon nanoscale transport beyond the relaxation-time approximation
نویسندگان
چکیده
The phonon Boltzmann transport equation (BTE) has been widely utilized to study thermal in solids. While for a number of materials the exact solution BTE obtained uniform heat flow, problems arising micro/nanoscale have analyzed within relaxation time approximation (RTA). Since RTA breaks down at temperatures low compared Debye temperature, this prevents an important class high temperature such as diamond, graphite, graphene, and some other two-dimensional materials. We present full scattering matrix formalism that goes beyond obtain Green's function linearized BTE, which leads explicit expression distribution field produced by arbitrary spatiotemporal sources unbounded medium. presented is capable describing wide range phenomena, from dissipation nanoscale hot spots propagation second sound waves. provide numerical results graphene spatially sinusoidal heating profile discuss importance using RTA.
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ژورنال
عنوان ژورنال: Physical review
سال: 2021
ISSN: ['0556-2813', '1538-4497', '1089-490X']
DOI: https://doi.org/10.1103/physrevb.104.245424