Quantum phase transition of Bose-Einstein condensates on a ring nonlinear lattice

TL;DR

This paper investigates phase transitions in a one-dimensional Bose-Einstein condensate on a ring with periodically modulated atomic interactions, revealing different transition orders and quantum behaviors through mean field and quantum simulations.

Contribution

It introduces a combined mean field and quantum approach to analyze phase transitions in BECs on a nonlinear lattice with periodic modulation.

Findings

Phase transitions vary in order depending on modulation period.

Mean field results are confirmed by quantum simulations.

Quantum behavior of the system shows rich phenomena.

Abstract

We study the phase transitions in a one dimensional Bose-Einstein condensate on a ring whose atomic scattering length is modulated periodically along the ring. By using a modified Bogoliubov method to treat such a nonlinear lattice in the mean field approximation, we find that the phase transitions are of different orders when the modulation period is 2 and greater than 2. We further perform a full quantum mechanical treatment based on the time-evolving block decimation algorithm which confirms the mean field results and reveals interesting quantum behavior of the system. Our studies yield important knowledge of competing mechanisms behind the phase transitions and the quantum nature of this system.