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arXiv · 2501.16430

Critical gate distance for Wigner crystallization in the two-dimensional electron gas

Agnes Valenti·Vladimir Calvera·Yubo Yang·Miguel A. Morales·Steven A. Kivelson·Ilya Esterlis·Shiwei Zhang
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Abstract

We report on the properties of the two-dimensional electron gas in a dual-gate geometry, using quantum Monte Carlo methods to obtain aspects of the phase diagram as a function of electron density and gate distance. We identify the critical gate distance below which the Wigner crystal phase disappears. For larger gate distances, the system undergoes a re-entrant transition from crystal to liquid at sufficiently low density. We also present preliminary evidence for a fully polarized ferromagnetic liquid state at low electron density and intermediate gate distances. The quantum Monte Carlo results are compared with simpler approximate methods, which are shown to be semi-quantitatively reliable for determining key features of the phase diagram. These methods are then used to obtain the phase boundary between the Wigner crystal and liquid in the single-gate geometry.

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Agnes Valenti, Vladimir Calvera, Yubo Yang, Miguel A. Morales, Steven A. Kivelson, Ilya Esterlis, Shiwei Zhang. 2025-01-27. Critical gate distance for Wigner crystallization in the two-dimensional electron gas. https://doi.org/10.1103/2qgp-v27h

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