Prerequisites for relevant spectral density and convergence of reduced density matrices at low temperatures

Akihito Ishizaki

doi:10.7566/jpsj.89.015001

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arXiv · 1911.12735

Prerequisites for relevant spectral density and convergence of reduced density matrices at low temperatures

Akihito Ishizaki

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Abstract

Hierarchical equations of motion approach with the Drude-Lorentz spectral density has been widely employed in investigating quantum dissipative phenomena. However, it is often computationally costly for low-temperature systems because a number of Matsubara frequencies are involved. In this note, we examine a prerequisite required for spectral density, and demonstrate that relevant spectral density may significantly reduce the number of Matsubara terms to obtain convergent results for low temperatures.

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Akihito Ishizaki. 2019-11-28. Prerequisites for relevant spectral density and convergence of reduced density matrices at low temperatures. https://doi.org/10.7566/jpsj.89.015001

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