Three-Dimensional Anderson Localization in Variable Scale Disorder

TL;DR

This study investigates how changing the scale of disorder affects three-dimensional Anderson localization in ultracold fermionic gases, revealing a linear relationship between disorder correlation length and localization size.

Contribution

It demonstrates the impact of variable-scale disorder on 3D Anderson localization using ultracold atoms and optical speckle potentials, with experimental verification.

Findings

Localized gas size increases linearly with speckle correlation length

Root-mean-square size scales with disorder correlation length

Qualitative agreement with weak scattering theory predictions

Abstract

We report on the impact of variable-scale disorder on 3D Anderson localization of a non-interacting ultracold atomic gas. A spin-polarized gas of fermionic atoms is localized by allowing it to expand in an optical speckle potential. Using a sudden quench of the localized density distribution, we verify that the density profile is representative of the underlying single-particle localized states. The geometric mean of the disordering potential correlation lengths is varied by a factor of four via adjusting the aperture of the speckle focusing lens. We observe that the root-mean-square size of the localized gas increases approximately linearly with the speckle correlation length, in qualitative agreement with the scaling predicted by weak scattering theory.