Beating the amorphous limit in thermal conductivity by superlattices design.

ABSTRACT: The value measured in the amorphous structure with the same chemical composition is often considered as a lower bound for the thermal conductivity of any material: the heat carriers are strongly scattered by disorder, and their lifetimes reach the minimum time scale of thermal vibrations. An appropriate design at the nano-scale, however, may allow one to reduce the thermal conductivity even below the amorphous limit. In the present contribution, using molecular-dynamics simulation and the Green-Kubo formulation, we study systematically the thermal conductivity of layered phononic materials (superlattices), by tuning different parameters that can characterize such structures. We have discovered that the key to reach a lower-than-amorphous thermal conductivity is to block almost completely t

SUBMITTER: Mizuno H 

PROVIDER: S-EPMC4571656 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature