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arXiv · 1503.02616

Effective One-Dimensional Models from Matrix Product States

Frederik Keim·Götz S. Uhrig
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Abstract

In this paper we present a method for deriving effective one-dimensional models based on the matrix product state formalism. It exploits translational invariance to work directly in the thermodynamic limit. We show, how a representation of the creation operator of single quasi-particles in both real and momentum space can be extracted from the dispersion calculation. The method is tested for the analytically solvable Ising model in a transverse magnetic field. Properties of the matrix product representation of the creation operator are discussed and validated by calculating the one-particle contribution to the spectral weight. Results are also given for the ground state energy and the dispersion.

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Frederik Keim, Götz S. Uhrig. 2015-03-09. Effective One-Dimensional Models from Matrix Product States. https://doi.org/10.1140/epjb/e2015-60188-0

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