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arXiv · 2108.08268

Quantum Circuits Reproduce Experimental Two-dimensional Many-body Localization Transition Point

Abstract

While many studies point towards the existence of many-body localization (MBL) in one dimension, the fate of higher-dimensional strongly disordered systems is a topic of current debate. The latest experiments as well as several recent numerical studies indicate that such systems behave many-body localized -- at least on practically relevant time scales. However, thus far, theoretical approaches have been unable to quantitatively reproduce experimentally measured MBL features -- an important requirement to demonstrate their validity. In this work, we use fermionic quantum circuits as a variational method to approximate the full set of eigenstates of two-dimensional MBL systems realized in fermionic optical lattice experiments. Using entanglement-based features, we obtain a phase transition point in excellent agreement with the experimentally measured value. Moreover, we calculate, the filling fraction-dependent MBL phase diagram, an important feature which has not been addressed in previous literature. We argue that our approach best captures the underlying charge-density-wave experiments and compute the mean localization lengths, which can be compared to future experiments.

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Joey Li, Amos Chan, Thorsten B. Wahl. 2021-08-18. Quantum Circuits Reproduce Experimental Two-dimensional Many-body Localization Transition Point. https://doi.org/10.1103/physrevb.109.l140202

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