Demonstration of Einstein-Podolsky-Rosen Steering Using Single-Photon Path Entanglement and Displacement-Based...

Area of Science:

• Quantum Information Science
• Quantum Optics
• Fundamental Physics

Background:

• Einstein-Podolsky-Rosen (EPR) steering is a key quantum phenomenon demonstrating non-locality.
• Single-photon path entanglement is a crucial resource for quantum information processing.
• Device-independent quantum protocols enhance security and robustness by minimizing assumptions about the devices used.

Purpose of the Study:

• To demonstrate the violation of an EPR steering inequality for single-photon path entanglement.
• To achieve a one-sided device-independent demonstration of entanglement.
• To explore the potential of path entanglement for future quantum technologies.

Main Methods:

• Utilized a high-rate source of heralded single-photon path-entangled states.
• Employed displacement-based detection with high-efficiency superconducting detectors.
• Implemented a scheme free of postselection to avoid the detection loophole.

Main Results:

• Successfully demonstrated the violation of an EPR steering inequality for single-photon path entanglement.
• Achieved a robust, loophole-free demonstration of entanglement in a one-sided device-independent manner.
• Confirmed the efficacy of displacement-based detection for verifying quantum correlations.

Conclusions:

• The results conclusively demonstrate single-photon entanglement in a one-sided device-independent scenario.
• This work validates path entanglement as a viable resource for quantum information.
• Opens avenues for the development of device-independent quantum technologies based on path entanglement.