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Updated: Jul 16, 2026
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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
How much entanglement can be generated between two atoms by detecting photons?
L Lamata1, J J García-Ripoll, J I Cirac
1Instituto de Matemáticas y Física Fundamental, CSIC, Serrano 113-bis, 28006 Madrid, Spain. lamata@imaff.cfmac.csic.es
Physical Review Letters
|March 16, 2007
Summary
Researchers demonstrate arbitrary entanglement between two atoms using photons and basic optics. This overcomes the one entanglement bit (ebit) limitation of current methods.
Area of Science:
- Quantum information science
- Atomic physics
- Quantum optics
Background:
- Entanglement is a key quantum resource.
- Current methods for entangling atoms are limited to one entanglement bit (ebit).
Purpose of the Study:
- To develop a method for achieving arbitrary entanglement between two atoms.
- To overcome the limitations of existing entanglement protocols.
Main Methods:
- Utilizing spontaneously emitted photons.
- Employing linear optics.
- Using single-photon sources.
- Performing projective measurements.
Main Results:
- Achieved an arbitrary amount of entanglement between two atoms.
- Demonstrated a method that surpasses the one-ebit restriction.
Conclusions:
- The proposed method offers a scalable approach to quantum entanglement.
- This technique advances the potential for complex quantum systems and communication.
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