Fidelity of a Bose-Einstein Condensate

TL;DR

This paper studies how the fidelity of a Bose-Einstein Condensate evolves over time, revealing different decay patterns depending on initial states and classical dynamics, with implications for experimental observation.

Contribution

It provides a detailed analysis of fidelity decay in Bose-Einstein Condensates, linking decay patterns to initial states and classical phase space regions, and suggests an experimental scheme.

Findings

Fidelity decays exponentially, Gaussian, or as a power-law depending on conditions.

High fidelity observed for initial states in regular phase space regions.

Decay patterns are influenced by the classical dynamics underlying the quantum system.

Abstract

We investigate fidelity, the Loschmidt echo, for a Bose-Einstein Condensate. It is found that the fidelity decays with time in various ways (exponential, Gaussian, and power-law), depending on the choice of initial coherent state as well as the parameters that determine properties of the underlying classical dynamics. Moreover, high fidelity is found for initial states lying in the regular region of a mixed-type phase space. A possible experimental scheme is suggested.