Macroscopic Superpositions of Phase States with Bose-Einstein Condensates

TL;DR

This paper demonstrates how Bose-Einstein condensates can be used to create and observe macroscopic quantum superpositions of phase states, with experimental signatures detectable through interference patterns, even considering decoherence effects.

Contribution

It introduces a method to generate and analyze macroscopic superpositions of phase states in BECs, highlighting their robustness and experimental feasibility.

Findings

Superpositions can be created in BECs trapped in periodic potentials.

Interference patterns reveal phase superpositions and depend on atom number parity.

Superpositions remain observable with current technology for small atom numbers.

Abstract

Quantum superpositions of macroscopically distinguishable states having distinct phases can be created with a Bose-Einstein condensate trapped in a periodic potential. The experimental signature is contained in the phase distribution of the interference patterns obtained after releasing the traps. Moreover, in the double well case, this distribution exhibits a dramatic dependence on the parity of the total number of atoms. We finally show that, for single well occupations up to a few hundred atoms, the macroscopic quantum superposition can be robust enough against decoherence to be experimentally revealable within current technology.