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arXiv · 2301.07288

Momentum-space signatures of the Anderson transition in a symplectic, two-dimensional, disordered ultracold gas

Ehsan Arabahmadi·Daniel Schumayer·Benoit Gremaud·Christian Miniatura·David A. W. Hutchinson
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Abstract

We study Anderson Localization in two dimensional (2D) disordered spin-orbit systems described by the Gaussian symplectic ensemble using momentum-space signatures such as the coherent backscattering (CBS) anti-peak, and the coherent forward scattering (CFS) peak. Significantly, these momentum-space features are readily accessible in ultracold atom experiments through absorption imaging after time-of-flight expansion. The critical exponent and mobility edge of the metal-insulator transition are successfully obtained in this model through a finite-time analysis of the CBS width. An anomalous residual diffusion, unique to 2D, is identified at the transition point where the system changes from a metal to an insulator. A spin localization phenomenon is also observed in the deep localized regime.

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Ehsan Arabahmadi, Daniel Schumayer, Benoit Gremaud, Christian Miniatura, David A. W. Hutchinson. 2023-01-18. Momentum-space signatures of the Anderson transition in a symplectic, two-dimensional, disordered ultracold gas. https://arxiv.org/abs/2301.07288

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