2019/07/31 by Kazuya Fujimoto, Kazunori Haneda, Kazue Kudo +1 · 1 citation
Physics and Astronomy · #cond-mat.quant-gas #nlin.PS #quant-ph
paper · pdf · doi:10.1103/physreva.101.023608
published as Phys. Rev. A 101, 023608 (2020) · 16 pages, 10 figures
arxiv created 2020/01/19 · arxiv updated 2020/02/26
We theoretically study the scale-invariant relaxation dynamics in segregating two-component Bose-Einstein condensates with large particle-number imbalance, and uncover that random walk of droplet for the minor component plays a fundamental role in the relaxation process. Our numerical simulations based on the binary Gross-Pitaevskii model reveal the emergence of the dynamical scaling during the relaxation, which is a hallmark of scale-invariant dynamics, in a correlation function for the minor condensate. Tracking exponents characterizing the dynamical scaling in time, we find out a crossover phenomenon that features the change in power exponents of the correlation length. To understand the fundamental mechanism inherent in the scale-invariant relaxation dynamics, we construct a random walk model for droplets. Employing the model, we analytically derive the 1/3 and 1/2 power laws and predict the crossover of the scaling. These exponents are in reasonable agreement with the values obtained in the numerical calculations. We also discuss a possible experimental setup for observing the scale-invariant dynamics.