# Experimentally Obtaining Maximal Coherence Via Assisted Distillation Pro cess

## TL;DR

This paper reports the first experimental realization of assisted quantum coherence distillation using linear optics, demonstrating maximal coherence extraction in pure states and increased coherence in mixed states with less resource demand.

## Contribution

It provides the first experimental demonstration of assisted coherence distillation, validating theoretical predictions and exploring coherence enhancement in pure and mixed bipartite quantum states.

## Key findings

- Maximal coherence achieved in pure states with one-copy protocol
- Distillable coherence can be increased in mixed states
- Less resource demand compared to entanglement distillation

## Abstract

Quantum coherence, which quantifies the superposition properties of a quantum state, plays an indispensable role in quantum resource theory. A recent theoretical work [Phys. Rev. Lett. \textbf{116}, 070402 (2016)] studied the manipulation of quantum coherence in bipartite or multipartite systems under the protocol Local Incoherent Operation and Classical Communication (LQICC). Here we present the first experimental realization of obtaining maximal coherence in assisted distillation protocol based on linear optical system. The results of our work show that the optimal distillable coherence rate can be reached even in one-copy scenario when the overall bipartite qubit state is pure. Moreover, the experiments for mixed states showed that distillable coherence can be increased with less demand than entanglement distillation. Our work might be helpful in the remote quantum information processing and quantum control.