Damping of Josephson oscillations in strongly correlated one-dimensional atomic gases

TL;DR

This paper investigates how quantum and thermal fluctuations cause damping of Josephson oscillations in strongly correlated one-dimensional bosonic gases, using exact solutions and a quantum-Langevin approach.

Contribution

It introduces a detailed analysis of damping mechanisms in strongly correlated 1D gases, applying the Tonks-Girardeau solution and quantum-Langevin methods to understand oscillation decay.

Findings

Damping depends on barrier height, interaction strength, and temperature.

Quantum and thermal fluctuations are the intrinsic cause of damping.

Results are applicable to particle-current oscillations in 1D rings.

Abstract

We study Josephson oscillations of two strongly correlated one-dimensional bosonic clouds separated by a localized barrier. Using a quantum-Langevin approach and the exact Tonks-Girardeau solution in the impenetrable-boson limit, we determine the dynamical evolution of the particle-number imbalance, displaying an effective damping of the Josephson oscillations which depends on barrier height, interaction strength and temperature. We show that the damping originates from the quantum and thermal fluctuations intrinsically present in the strongly correlated gas. Thanks to the density-phase duality of the model, the same results apply to particle-current oscillations in a one-dimensional ring where a weak barrier couples different angular momentum states.