Long time non-equilibrium dynamics of binary Bose condensates

TL;DR

This paper investigates the slow, logarithmic growth of domains during the non-equilibrium phase separation of binary Bose condensates after a quench, revealing challenges in reaching equilibrium in isolated quantum systems.

Contribution

It provides new insights into the slow dynamics and domain growth behavior of binary Bose fluids following a quench across the phase boundary.

Findings

Short-range correlations form rapidly after the quench.

Domain growth is much slower than conventional theories predict.

Growth dynamics exhibit logarithmic slowing over time.

Abstract

We explore the out-of-equilibrium temporal dynamics of demixing and phase separation in a two dimensional binary Bose fluid at zero temperature, following a sudden quench across the miscible-immiscible phase boundary. On short timescales, the system rapidly settles into a steady state characterized by short-range correlations in the relative density. The subsequent dynamics is extremely slow: domains of the relative density appear to grow with time, however, the rate of growth is much slower than that predicted by conventional theories of phase ordering kinetics. Moreover, we find that the growth dynamics slows down with increasing time, and is consistent with logarithmic growth. Our study sheds light on ongoing investigations of how isolated quantum systems approach equilibrium, and indicates that studying the quantum phase diagram of the binary Bose fluids following a quench, may be difficult due to equilibration problems.