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arXiv · 1911.01159

Evaluation of time-dependent correlators after a local quench in iPEPS: hole motion in the t-J model

C. Hubig·A. Bohrdt·M. Knap·F. Grusdt·J. I. Cirac
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Abstract

Infinite projected entangled pair states (iPEPS) provide a convenient variational description of infinite, translationally-invariant two-dimensional quantum states. However, the simulation of local excitations is not directly possible due to the translationally-invariant ansatz. Furthermore, as iPEPS are either identical or orthogonal, expectation values between different states as required during the evaluation of non-equal-time correlators are ill-defined. Here, we show that by introducing auxiliary states on each site, it becomes possible to simulate both local excitations and evaluate non-equal-time correlators in an iPEPS setting under real-time evolution. We showcase the method by simulating the t-J model after a single hole has been placed in the half-filled antiferromagnetic background and evaluating both return probabilities and spin correlation functions, as accessible in quantum gas microscopes.

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C. Hubig, A. Bohrdt, M. Knap, F. Grusdt, J. I. Cirac. 2020-01-14. Evaluation of time-dependent correlators after a local quench in iPEPS: hole motion in the t-J model. https://doi.org/10.21468/scipostphys.8.2.021

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