The dynamics of coherence between coupled and decoupled one-dimensional quasicondensates

TL;DR

This paper investigates the decoherence dynamics of coupled and decoupled one-dimensional quasicondensates, revealing that strong coupling does not always prevent decoherence and that density fluctuations play a crucial role.

Contribution

It demonstrates the sub-exponential decoherence behavior and proposes an experiment to study coherence growth, highlighting the impact of temperature and density fluctuations.

Findings

Decoherence can occur even with strong coupling at high temperatures or low densities.

Coherence growth between initially incoherent quasicondensates is slow and density-dependent.

Final coherence levels are strongly influenced by density fluctuations.

Abstract

We reproduce the sub-exponential decoherence of one-dimensional quasicondensates observed in recent experiments. Counter-intuitively, the quasicondensates may decohere even when stongly coupled, if the temperature is large enough or the peak density is low enough to allow significant density fluctuations. We also propose an experiment to investigate the growth of coherence between two initially incoherent quasicondensates. We predict that the coherence will rise on a much slower timescale, and the final coherence again depends strongly on the density fluctuations.