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Nonclassicality by Local Gaussian Unitary Operations for Gaussian States.
Yangyang Wang1, Xiaofei Qi1,2, Jinchuan Hou1,3
1Department of Mathematics, Shanxi University, Taiyuan 030006, China.
Entropy (Basel, Switzerland)
|December 3, 2020
Summary
A new measure of nonclassicality (N) quantifies quantum correlations in Gaussian states. This measure is faithful, always less than 1, and helps establish entanglement criteria for quantum information processing.
Area of Science:
- Quantum Information Science
- Quantum Optics
- Quantum Many-Body Systems
Background:
- Characterizing quantum correlations is crucial for quantum information processing.
- Existing measures may not fully capture the nuances of quantum correlations in Gaussian states.
Purpose of the Study:
- Introduce a novel measure of nonclassicality (N) for bipartite Gaussian states.
- Develop a faithful and computable measure of quantum correlations.
Main Methods:
- Defined nonclassicality (N) using local Gaussian unitary operations.
- Derived an explicit formula for N in (1+1)-mode Gaussian states.
- Provided an estimate for N in (n+m)-mode Gaussian states.
Main Results:
- Established N as a faithful quantum correlation measure for Gaussian states, ranging from 0 to 1.
- Demonstrated that N is present in all non-product Gaussian states.
- Developed a criterion for entanglement based on the measure N.
- Compared N with other quantum correlation measures like entanglement, Gaussian discord, and Gaussian geometric discord.
Conclusions:
- The introduced measure N provides a robust tool for quantifying quantum correlations in Gaussian states.
- N offers a new perspective on entanglement detection and characterization.
- This work contributes to a deeper understanding of quantum correlations in continuous-variable systems.
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