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arXiv:2509.07312 · Physical Review A

Coherent transport in two-dimensional disordered potentials under spatially uniform SU ( 2 ) gauge fields

Masataka Kakoi, Christian Miniatura, Keith Slevin

Published Mar 20, 2026• 2 citations
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Abstract

We study interference effects in the dynamics of a spin-$1/2$ particle propagating in two dimensions in a disordered potential and subject to a generalized spin-orbit coupling. With the particle initially in a spin-polarized plane wave state, in the short-time regime, before the spin and momentum distributions reach their steady states, we observe a transient backscattering peak offset from the exact backscattering direction, coexisting with a coherent backscattering dip. We present an intuitive explanation of this momentum offset using a non-Abelian gauge transformation. We also describe the full time evolution of the transient peak, from its buildup to its decay with a precise prediction of the dephasing time within a perturbative framework for multiple scattering. Our results can be applied to general spatially uniform SU(2) gauge fields, including the synthetic gauge field in ultracold atoms.

DOI
10.1103/kdcq-9q67

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