[20p-234B-1~17] 22.1 Joint Session M "Phonon Engineering"

[20p-234B-15] Phonon Blocking due to Geometrically-Engineered Self-Energy

〇Yohei Nakamura¹, Kiminori Hattori¹ (1.Osaka Univ.)

Keywords:phonon transport, self-energy, Landauer formula

Because of the presence of robust massless modes with no excitation gap, the heat current carried by phonons tends to survive at low temperatures even when scattering mechanisms are incorporated into the system. This becomes a fundamental obstacle to thermoelectric applications at low temperatures. In this study, we investigate the effect of self-energy on phonon transport in mesoscopic systems coupled to leads or probes in various geometries. An analytic theory derived from a minimal model consisting of a harmonic chain shows that the geometrically-engineered self-energy enables us to suppress low-temperature phonon transport. It is also demonstrated from numerical calculations that this scheme for phonon blocking is viable for realistic systems in higher dimensions.