Anomalous quantum heat transport in a one-dimensional harmonic chain with random couplings

作者:Yan Yonghong*; Zhao Hui
来源:Journal of Physics: Condensed Matter , 2012, 24(27): 275401.
DOI:10.1088/0953-8984/24/27/275401

摘要

We investigate quantum heat transport in a one-dimensional harmonic system with random couplings. In the presence of randomness, phonon modes may normally be classified as ballistic, diffusive or localized. We show that these modes can roughly be characterized by the local nearest-neighbor level spacing distribution, similarly to their electronic counterparts. We also show that the thermal conductance G(th) through the system decays rapidly with the system size (G(th) similar to L-alpha). The exponent alpha strongly depends on the system size and can change from alpha < 1 to alpha > 1 with increasing system size, indicating that the system undergoes a transition from a heat conductor to a heat insulator. This result could be useful in thermal control of low-dimensional systems.

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