arXiv:2004.05017 · Physical review. E

Steady-state quantum transport through an anharmonic oscillator strongly coupled to two heat reservoirs

Tianqi Chen, Vinitha Balachandran, Chu Guo, Dario Poletti

Published Jul 31, 2020• 24 citations

Abstract

We investigate the transport properties of an anharmonic oscillator, modeled by a single-site Bose-Hubbard model, coupled to two different thermal baths using the numerically exact thermofield based chain-mapping matrix product states (TCMPS) approach. We compare the effectiveness of TCMPS to probe the nonequilibrium dynamics of strongly interacting system irrespective of the system-bath coupling against the global master equation approach in Gorini-Kossakowski-Sudarshan-Lindblad form. We discuss the effect of on-site interactions, temperature bias as well as the system-bath couplings on the steady-state transport properties. Last, we also show evidence of non-Markovian dynamics by studying the nonmonotonicity of the time evolution of the trace distance between two different initial states.

DOI: 10.1103/physreve.102.012155

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