arXiv:2002.10475 · Science

Topological pumping of a 1D dipolar gas into strongly correlated prethermal states

Wil Kao, Kuan-Yu Li, Kuan-Yu Lin, Sarang Gopalakrishnan, Benjamin Lev

Published Jan 14, 2021• 82 citations

Abstract

Long-lived excited states of interacting quantum systems that retain quantum correlations and evade thermalization are of great fundamental interest. We create nonthermal states in a bosonic one-dimensional (1D) quantum gas of dysprosium by stabilizing a super-Tonks-Girardeau gas against collapse and thermalization with repulsive long-range dipolar interactions. Stiffness and energy-per-particle measurements show that the system is dynamically stable regardless of contact interaction strength. This enables us to cycle contact interactions from weakly to strongly repulsive, then strongly attractive, and finally weakly attractive. We show that this cycle is an energy-space topological pump (caused by a quantum holonomy). Iterating this cycle offers an unexplored topological pumping method to create a hierarchy of increasingly excited prethermal states.

DOI: 10.1126/science.abb4928

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