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arXiv · 1811.04899

Gaussian states for the variational study of (1+1)-dimensional lattice gauge models

P. Sala·T. Shi·S. Kühn·M. C. Bañuls·E. Demler·J. I. Cirac
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Abstract

We introduce a variational ansatz based on Gaussian states for (1+1)-dimensional lattice gauge models. To this end we identify a set of unitary transformations which decouple the gauge degrees of freedom from the matter fields. Using our ansatz, we study static aspects as well as real-time dynamics of string breaking in two (1+1)-dimensional theories, namely QED and two-color QCD. We show that our ansatz captures the relevant features and is in excellent agreement with data from numerical calculations with tensor networks.

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P. Sala, T. Shi, S. Kühn, M. C. Bañuls, E. Demler, J. I. Cirac. 2018-11-12. Gaussian states for the variational study of (1+1)-dimensional lattice gauge models. https://doi.org/10.22323/1.334.0230

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