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Tensor Product Variational Formulation for Quantum Systems

Y. Nishio·N. Maeshima·A. Gendiar·T. Nishino
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Abstract

We consider a variational problem for the two-dimensional (2D) Heisenberg and XY models, using a trial state which is constructed as a 2D product of local weights. Variational energy is calculated by use of the the corner transfer matrix renormalization group (CTMRG) method, and its upper bound is surveyed. The variational approach is a way of applying the density matrix renormalization group method (DMRG) to infinite size 2D quantum systems.

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Y. Nishio, N. Maeshima, A. Gendiar, T. Nishino. 2004-01-08. Tensor Product Variational Formulation for Quantum Systems. https://arxiv.org/abs/cond-mat/0401115

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