Universality in nonlinear passage through the miscible-immiscible phase transition in two component Bose-Einstein condensates

TL;DR

This paper explores the universal dynamics and defect formation during the phase transition in two-component Bose-Einstein condensates, revealing how nonlinear effects influence defect suppression and critical behavior.

Contribution

It introduces a detailed analysis of defect formation and critical exponents in nonlinear quenched BECs, highlighting the universality and suppression mechanisms of domain defects.

Findings

Power-law relations between defect density and quench time

Critical exponents are insensitive to nonlinear coefficients

Large nonlinear coefficients suppress domain defects

Abstract

In this study, we investigate the formation of domain defects and the universal critical real-time dynamics in a two-component Bose-Einstein condensate with nonlinear quenching across the miscible-immiscible phase transition. By analyzing the Bogoliubov excitations, we obtain the power-law relations among the defect density, the phase transition delay and the quench time near the phase transition. Moreover, by simulating the real-time dynamics across the miscible-immiscible phase transition, we clearly show the formation of domain defects and the delay of the phase transition. Furthermore, we find that the domain defects are suppressed by large nonlinear coefficients and long quench times. To accurately characterize the domain defects, we quantify the defect excitations using the correlation length and the domain number. In addition, by combining the power-law relations between the phase transition delay and the quench time, we extract the critical exponents for different nonlinear coefficients. Our study not only confirms that the critical exponents do not sensitively depend on the nonlinear quenches but also provides a dynamic path toward the suppression of nonadiabatic excitation.