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arXiv · 1312.6044

Matrix product state formulation of frequency-space dynamics at finite temperatures

Alexander C. Tiegel·Salvatore R. Manmana·Thomas Pruschke·Andreas Honecker
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Abstract

We present a flexible density-matrix renormalization group approach to calculate finite-temperature spectral functions of one-dimensional strongly correlated quantum systems. The method combines the purification of the finite-temperature density operator with a moment expansion of the Green's function. Using this approach, we study finite-temperature properties of dynamical spectral functions of spin-1/2 XXZ chains with Dzyaloshinskii-Moriya interactions in magnetic fields and analyze the effect of these symmetry breaking interactions on the nature of the finite-temperature dynamic spin structure factor.

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Alexander C. Tiegel, Salvatore R. Manmana, Thomas Pruschke, Andreas Honecker. 2013-12-20. Matrix product state formulation of frequency-space dynamics at finite temperatures. https://doi.org/10.1103/physrevb.90.060406

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