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Real-time dynamics at finite temperature by DMRG: A path-integral approach

J. Sirker·A. Klümper
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Abstract

We propose a path-integral variant of the DMRG method to calculate real-time correlation functions at arbitrary finite temperatures. To illustrate the method we study the longitudinal autocorrelation function of the $XXZ$-chain. By comparison with exact results at the free fermion point we show that our method yields accurate results up to a limiting time which is determined by the spectrum of the reduced density matrix.

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J. Sirker, A. Klümper. 2005-04-05. Real-time dynamics at finite temperature by DMRG: A path-integral approach. https://doi.org/10.1103/physrevb.71.241101

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