Competition and interplay between topology and quasi-periodic disorder in Thouless pumping of ultracold atoms

Robustness against perturbations lies at the heart of topological phenomena. If, however, a perturbation such as disorder becomes dominant, it may cause a topological phase transition between topologically non-trivial and trivial phases. Here we experimentally reveal the competition and interplay between topology and quasi-periodic disorder in a Thouless pump realized with ultracold atoms in an optical lattice, by creating a quasi-periodic potential from weak to strong regimes in a controllable manner. We demonstrate a disorder-induced pumping in which the presence of quasi-periodic disorder can induce a non-trivial pump for a specific pumping sequence, whereas no pump is observed in the clean limit. Our highly controllable system, which can also straightforwardly incorporate interatomic interaction, could be a unique platform for studying various disorder-related effects in a wide range of topological quantum phenomena. Topologically protected charge transport, known as Thouless pumping, is realized with cold atoms trapped in quasi-periodic disordered potentials. The pumping is disorder-dependent, illustrating the influence of disorder on the topological properties.

Automated summary

The influence of disorder on topological phenomena is significant, showing competition and interaction in experiments. Topologically protected charge transport, known as Thouless pumping, is achieved with disorder-dependent effects on the topological properties.