Stabilizing confined quasiparticle dynamics in one-dimensional polar lattice gases

TL;DR

This study explores how small disorder can stabilize localized quasiparticle dynamics in one-dimensional polar lattice gases, preventing thermalization and enhancing dynamical confinement through the interplay of dipole interactions and disorder.

Contribution

It reveals that small disorder stabilizes localized quasiparticle dynamics in polar gases, extending understanding of disorder effects in quantum many-body systems.

Findings

Disorder stabilizes localized dynamics against thermalization.

Effective second-order hopping is suppressed by disorder.

Disorder-related fluctuations are reduced by dipole-dipole interactions.

Abstract

The disorder-free localization that occurred in the study of relaxation dynamics in far-from-equilibrium quantum systems has been widely explored. Here we investigate the interplay between the dipole-dipole interaction (DDI) and disorder in the hard-core polar bosons in a one-dimensional lattice. We find that the localized dynamics will eventually thermalize in the clean gas, but can be stabilized with the existence of a small disorder proportional to the inverse of DDI strength. From the effective dimer Hamiltonian, we show that the effective second-order hopping of quasiparticles between nearest-neighbor sites is suppressed by the disorder with strength similar to the effective hopping amplitude. The significant gap between the largest two eigenvalues of the entanglement spectrum indicates the dynamical confinement. We also find that the disorder related sample-to-sample fluctuation is suppressed by the DDI. Finally, we extend our research from the uncorrelated random disorder to the correlated quasiperiodic disorder and from the two-dimer model to the half-filling system, obtaining similar results.