Efimov Physics in Quenched Unitary Bose Gases

TL;DR

This paper investigates how Efimov physics influences the early dynamics and decay rates of quenched unitary Bose gases, revealing density-dependent Efimov oscillations and deviations from scale invariance.

Contribution

It introduces a local density model to analyze three-body decay and Efimov state growth, highlighting the breakdown of continuous scale-invariance in quenched Bose gases.

Findings

Density-dependent Efimov oscillations in decay rates

Early-time growth of Efimov states post-quench

Departure from Landau-Zener behavior with varying sweep rates

Abstract

We study the impact of three-body physics in quenched unitary Bose gases, focusing on the role of the Efimov effect. Using a local density model, we solve the three-body problem and determine three-body decay rates at unitary, finding density-dependent, log-periodic Efimov oscillations, violating the expected continuous scale-invariance in the system. We find that the breakdown of continuous scale-invariance, due to Efimov physics, manifests also in the earliest stages of evolution after the interaction quench to unitarity, where we find the growth of a substantial population of Efimov states for densities in which the interparticle distance is comparable to the size of an Efimov state. This agrees with the early-time dynamical growth of three-body correlations at unitarity [Colussi {\em et al}., Phys. Rev. Lett. 120, 100401 (2018)]. By varying the sweep rate away from unitarity, we also find a departure from the usual Landau-Zener analysis for state transfer when the system is allowed to evolve at unitarity and develop correlations.