Quantum Theory of a Bose-Einstein Condensate out of Equilibrium

TL;DR

This paper develops a quantum theoretical model describing how a Bose-Einstein condensate out of equilibrium interacts with an external field, revealing modified Rabi oscillations, collapse, and revival phenomena influenced by atomic interactions.

Contribution

It introduces a quantum framework for BEC out of equilibrium interacting with external fields, highlighting the effects of atomic interactions on Rabi oscillations and collapse-revival dynamics.

Findings

Atomic interactions reduce the Rabi frequency.

Collapse and revival phenomena are influenced by atomic interactions.

External field granularity affects oscillation dynamics.

Abstract

We consider the interaction between a single-mode quantized perturbing external field and a Bose-Einstein condensate (BEC) out of equilibrium. The usual Rabi type oscillations between the ground and the excited state of the coherent topological modes are observed with a Rabi frequency modified by the two-body atomic interactions. Taking into account the granular structure of the external perturbing field reveals the well know phenomena of collapse and revival of the Rabi oscillations. In particular we find that atomic interactions reduce the Rabi frequency and also affect the collapse and revival sequence.