# Demonstration of Einstein-Podolsky-Rosen Steering with Enhanced Subchannel Discrimination

## TL;DR

This paper experimentally demonstrates EPR steering by designing subchannels for a quantum channel, showing that steerable states enhance subchannel discrimination success, thus providing an operational demonstration of EPR steering.

## Contribution

The work constructs feasible subchannels for a quantum channel and experimentally demonstrates enhanced discrimination using steerable states, advancing operational understanding of EPR steering.

## Key findings

- Steerable states improve subchannel discrimination success probability.
- Experimental realization of the SD task with enhanced performance.
- Provides a concrete operational demonstration of EPR steering.

## Abstract

Einstein-Podolsky-Rosen (EPR) steering describes a quantum nonlocal phenomenon in which one party can nonlocally affect the other's state through local measurements. It reveals an additional concept of quantum nonlocality, which stands between quantum entanglement and Bell nonlocality. Recently, a quantum information task named as subchannel discrimination (SD) provides a necessary and sufficient characterization of EPR steering. The success probability of SD using steerable states is higher than using any unsteerable states, even when they are entangled. However, the detailed construction of such subchannels and the experimental realization of the corresponding task are still technologically challenging. In this work, we designed a feasible collection of subchannels for a quantum channel and experimentally demonstrated the corresponding SD task where the probabilities of correct discrimination are clearly enhanced by exploiting steerable states. Our results provide a concrete example to operationally demonstrate EPR steering and shine a new light on the potential application of EPR steering.