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arXiv · 0905.3225

Simulation of two dimensional quantum systems on an infinite lattice revisited: corner transfer matrix for tensor contraction

Roman Orus·Guifre Vidal
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Abstract

An extension of the projected entangled-pair states (PEPS) algorithm to infinite systems, known as the iPEPS algorithm, was recently proposed to compute the ground state of quantum systems on an infinite two-dimensional lattice. Here we investigate a modification of the iPEPS algorithm, where the environment is computed using the corner transfer matrix renormalization group (CTMRG) method, instead of using one-dimensional transfer matrix methods as in the original proposal. We describe a variant of the CTMRG that addresses different directions of the lattice independently, and use it combined with imaginary time evolution to compute the ground state of the two-dimensional quantum Ising model. Near criticality, the modified iPEPS algorithm is seen to provide a better estimation of the order parameter and correlators.

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Roman Orus, Guifre Vidal. 2009-08-14. Simulation of two dimensional quantum systems on an infinite lattice revisited: corner transfer matrix for tensor contraction. https://doi.org/10.1103/physrevb.80.094403

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