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arXiv · 2104.08608

Efficient Time-Domain Approach for Linear Response Functions

Michel Panhans·Frank Ortmann
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Abstract

We derive the general Kubo formula in a form that solely utilizes the time evolution of displacement operators. The derivation is based on the decomposition of the linear response function into its time symmetric and time anti-symmetric part. We relate this form to the well-known fluctuation-dissipation formula and discuss theoretical and numerical aspects of it. The approach is illustrated with an analytical example for magnetic resonance as well as a numerical example where we analyze the electrical conductivity tensor and the Chern insulating state of the disordered Haldane model. We introduce a highly efficient time-domain approach that describes the quantum dynamics of the resistivity of this model with an at least 1000-fold better performance in comparison to existing time-evolution schemes.

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Michel Panhans, Frank Ortmann. 2021-04-17. Efficient Time-Domain Approach for Linear Response Functions. https://doi.org/10.1103/physrevlett.127.016601

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