Temperature oscillation in one-dimensional superlattice induced by phonon localization

Abstract

Abstract Thermal transport properties and thermodynamic quantities often present anomalous behaviors in low-dimensional systems. In this paper, it is found that temperature oscillates spatially in one-dimensional harmonic and weakly anharmonic superlattice. With the increase of anharmonicity, the temperature oscillation gradually disappears and a normal temperature gradient forms. Further analysis reveals that the formation of temperature oscillation is due to the localization of high frequency phonons which cannot be thermalized. Moreover, the localized modes interact weakly with heat reservoirs, thus, their contributions to local temperature remain negligible while varying the temperatures of heat reservoirs. The oscillated temperature profile is in a good agreement with Visscher’s formula. The temperature oscillation discovered here has great potential in applications of phononic devices for heat manipulation.