Low-temperature density matrix renormalization group using regulated polynomial expansion

Shigetoshi Sota; Takami Tohyama

doi:10.1103/physrevb.78.113101

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arXiv · 0806.3352

Low-temperature density matrix renormalization group using regulated polynomial expansion

Shigetoshi Sota·Takami Tohyama

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Abstract

We propose a density matrix renormalization group (DMRG) technique at finite temperatures. As is the case of the ground state DMRG, we use a single-target state that is calculated by making use of a regulated polynomial expansion. Both static and dynamical quantities are obtained after a random-sampling and averaging procedure. We apply this technique to the one-dimensional Hubbard model at half filling and find that this gives excellent results at low temperatures.

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Shigetoshi Sota, Takami Tohyama. 2008-09-01. Low-temperature density matrix renormalization group using regulated polynomial expansion. https://doi.org/10.1103/physrevb.78.113101

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