Topology Induced Spatial Bose-Einstein Condensation for Bosons on Star-Shaped Optical Networks

TL;DR

This paper demonstrates how the topology of a star-shaped optical network induces a localized Bose-Einstein condensate, with the critical temperature depending on network geometry and Josephson energy, revealing a novel topological control of quantum states.

Contribution

It introduces the concept of topology-induced Bose-Einstein condensation in star-shaped optical networks, linking network geometry to condensation properties.

Findings

Critical temperature depends on number of star arms and Josephson energy.

Ground state localization around the star center.

Non-condensate fraction scales with reduced temperature T/T_c.

Abstract

New coherent states may be induced by pertinently engineering the topology of a network. As an example, we consider the properties of non-interacting bosons on a star network, which may be realized with a dilute atomic gas in a star-shaped deep optical lattice. The ground state is localized around the star center and it is macroscopically occupied below the Bose-Einstein condensation temperature T_c. We show that T_c depends only on the number of the star arms and on the Josephson energy of the bosonic Josephson junctions and that the non-condensate fraction is simply given by the reduced temperature T/T_c.