Theoretical study of thermal diode

Abstract

We successfully construct an efficient thermal diode by coupling two dissimilar anharmonic lattices ( Frenkel-Kontorova and Fermi-Pasta-Ulam lattices ) and generalize it from one dimensional to three dimensional systems. The underlying mechanism is explored both analytically and numerically. We make it clear that the broken of the spatial symmetry is necessary to make the heat flow asymmetric, while the introduction of the nonlinearity allows us to adjust parameters to get the vibration spectra match or mismatch by reversing the temperature gradient and consequently result in thermal rectification. Our study on thermal rectifying effect in dissimilar anharmonic lattices has general meaning. It may offer useful guidance and meaningful suggestions when designing thermal rectifier with other different materials or different structures.