# Mesoscopic quantum superpositions in bimodal Bose-Einstein condensates: decoherence and strategies to counteract it

## TL;DR

This paper investigates how mesoscopic superpositions in bimodal Bose-Einstein condensates are generated, how decoherence affects them, and proposes methods to mitigate decoherence effects for better quantum state control.

## Contribution

It provides a full multimode theoretical analysis of mesoscopic superpositions, including decoherence effects and strategies for their preparation and preservation.

## Key findings

- Decoherence due to particle losses significantly impacts phase revival.
- Preexisting thermal fluctuations reduce cat fidelities.
- Proposed preparation procedures improve superposition robustness.

## Abstract

We study theoretically the interaction-induced generation of mesoscopic coherent spin state superpositions (small cat states) from an initial coherent spin state in bimodal Bose-Einstein condensates and the subsequent phase revival, including decoherence due to particle losses and fluctuations of the total particle number. In a full multimode description, we propose a preparation procedure of the initial coherent spin state and we study the effect of preexisting thermal fluctuations on the phase revival, and on the spin and orbito-spinorial cat fidelities.