Dynamics of dissipative Bose-Einstein condensation

TL;DR

This paper investigates the real-time dissipative dynamics of a quantum spin or hard-core boson system on a lattice, revealing how it evolves into a macroscopic entangled Bose-Einstein condensate and analyzing the associated time scales and entanglement properties.

Contribution

It introduces a detailed analysis of dissipative quantum dynamics leading to Bose-Einstein condensation and proposes a new method to generate macroscopic entanglement.

Findings

Identification of characteristic time scales for the dissipative process

Finite-size scaling behavior of the dynamics

Introduction of cumulative entanglement distribution as a measure

Abstract

We resolve the real-time dynamics of a purely dissipative $s = 1/2$ quantum spin or, equivalently, hard-core boson model on a hypercubic $d$-dimensional lattice. The considered quantum dissipative process drives the system to a totally symmetric macroscopic superposition in each of the $S^3$ sectors. Different characteristic time scales are identified for the dynamics and we determine their finite-size scaling. We introduce the concept of cumulative entanglement distribution to quantify multiparticle entanglement and show that the considered protocol serves as an efficient method to prepare a macroscopically entangled Bose-Einstein condensate.