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Updated: Jan 3, 2026
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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
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Entropic nonclassicality and quantum non-Gaussianity tests via beam splitting
Jiyong Park1, Jaehak Lee2, Hyunchul Nha3,4
1School of Basic Sciences, Hanbat National University, Daejeon, 34158, Korea. jiyong.park@hanbat.ac.kr.
Scientific Reports
|November 30, 2019
Summary
We introduce new criteria to detect nonclassical light states using entropy measurements. This method is more sensitive than current tests and can identify quantum resources for entanglement and steering.
Area of Science:
- Quantum Optics
- Quantum Information Theory
Background:
- Classical light states exhibit predictable behavior under loss.
- Detecting nonclassicality is crucial for quantum technologies.
Purpose of the Study:
- To develop novel entropic criteria for identifying nonclassical states of light.
- To provide a practical method for testing these criteria using standard quantum optical setups.
Main Methods:
- Utilizing the property that classical state entropy is non-increasing under loss.
- Employing homodyne detection with beam splitting for measurements.
- Extending criteria to detect quantum non-Gaussianity and entanglement.
Main Results:
- Proposed entropic criteria are strictly stronger than variance-based squeezing conditions.
- The method successfully identifies quantum non-Gaussian states.
- Demonstrated application in identifying resource states for quantum steering and EPR paradox.
Conclusions:
- Entropic nonclassicality criteria offer a robust and sensitive method for characterizing quantum states of light.
- The proposed technique is experimentally feasible with current technology.
- These criteria advance the understanding and generation of quantum entanglement and steering.
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