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arXiv · 0902.4475

Minimally entangled typical quantum states at finite temperature

Steven R. White
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Abstract

We introduce a class of states, called minimally entangled typical thermal states (METTS), designed to resemble a typical state of a quantum system at finite temperature with a bias towards classical (minimally entangled) properties. These states reveal in an intuitive way properties such as short-range order which may be hidden in correlation functions. An algorithm is presented which, when used with the density matrix renormalization group (DMRG), is faster by a factor of $10^3 - 10^{10}$ than previous heat-bath approaches for thermally averaged quantities.

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Steven R. White. 2009-02-25. Minimally entangled typical quantum states at finite temperature. https://doi.org/10.1103/physrevlett.102.190601

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