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Updated: Jul 10, 2026
07:56
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Demonstration of a stable atom-photon entanglement source for quantum repeaters
Shuai Chen1, Yu-Ao Chen, Bo Zhao
1Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Philosophenweg 12, 69120 Heidelberg, Germany.
Physical Review Letters
|November 13, 2007
Summary
Researchers developed a new method for robust atom-photon entanglement using a single laser and quantum memory. This entanglement persists for over 20 microseconds, proving its stability for quantum repeaters.
Area of Science:
- Quantum Information Science
- Atomic Physics
- Quantum Optics
Background:
- Entanglement is crucial for quantum information processing.
- Robust atom-photon entanglement is essential for quantum networks.
Purpose of the Study:
- To demonstrate an efficient and robust method for creating atom-photon entanglement.
- To investigate the storage time and stability of the generated entanglement.
Main Methods:
- Utilizing a single laser beam to excite an atomic ensemble.
- Employing two Raman field modes for entanglement generation.
- Incorporating quantum memory for entanglement storage.
Main Results:
- Successfully generated robust entanglement between an atomic and a photonic qubit.
- Demonstrated entanglement storage for over 20.5 microseconds.
- Verified entanglement through the violation of a Bell's inequality.
Conclusions:
- The developed entanglement procedure is a viable building block for quantum repeaters.
- The method can be extended for generating high-dimensional atom-photon entanglement.
- This work advances the development of robust quantum communication technologies.
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