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arXiv · 1805.10161

Extending the hierarchical quantum master equation approach to low temperatures and realistic band structures

Andre Erpenbeck·Christian Hertlein·Christian Schinabeck·Michael Thoss
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Abstract

The hierarchical quantum master equation (HQME) approach is an accurate method to describe quantum transport in interacting nanosystems. It generalizes perturbative master equation approaches by including higher-order contributions as well as non-Markovian memory and allows for the systematic convergence to the numerically exact result. As the HQME method relies on a decomposition of the bath correlation function in terms of exponentials, however, its application to systems at low temperatures coupled to baths with complexer band structures has been a challenge. In this publication, we outline an extension of the HQME approach, which uses a re-summation over poles and can be applied to calculate transient currents at a numerical cost that is independent of temperature and band structure of the baths. We demonstrate the performance of the extended HQME approach for noninteracting tight-binding model systems of increasing complexity as well as for the spinless Anderson-Holstein model.

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Andre Erpenbeck, Christian Hertlein, Christian Schinabeck, Michael Thoss. 2018-05-25. Extending the hierarchical quantum master equation approach to low temperatures and realistic band structures. https://doi.org/10.1063/1.5041716

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