# Distillation of maximally correlated bosonic matter from many-body quantum coherence

## TL;DR

This paper develops a new resource theory for quantum coherence in bosonic systems, enabling analysis of coherence and distillation of maximally correlated states in many-body quantum systems.

## Contribution

It introduces the QCRTF framework that is basis-independent and applicable to both particle number conserving and indefinite particle number states.

## Key findings

- QCRTF connects DV and CV bosonic coherence analyses.
- Optimal distillation rate of maximally correlated states is calculated.
- Uniform superposition of maximally correlated states can be generated efficiently.

## Abstract

We construct quantum coherence resource theories in symmetrized Fock space (QCRTF), thereby providing an information-theoretic framework that connects analyses of quantum coherence in discrete-variable (DV) and continuous variable (CV) bosonic systems. Unlike traditional quantum coherence resource theories, QCRTF can be made independent of the single-particle basis and allow to quantify coherence within and between particle number sectors. For example, QCRTF can be formulated in such a way that neither Bose-Einstein condensates nor Heisenberg-Weyl coherent states are considered as quantum many-body coherence resources, whereas spin-squeezed and quadrature squeezed states are. The QCRTF framework is utilized to calculate the optimal asymptotic distillation rate of maximally correlated bosonic states both for particle number conserving resource states and resource states of indefinite particle number. In particular, we show how to generate a uniform superposition of maximally correlated bosonic states from a state of maximal bosonic coherence with asymptotically unit efficiency using only free operations in the QCRTF.