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arXiv · 2311.17399

A Sensitive Quantumness Measure for One-Dimensional Continuous-Variable Systems

Ole Steuernagel·Hsien-Yi Hsieh·Yi-Ru Chen·Ray-Kuang Lee
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Abstract

For one-dimensional continuous-variable quantum systems such as single-mode quantum optical systems, we give a quantification of the quantumness of such a system's state, {\rho}, by introducing the measure of quantumness, {\Xi}, which works for all states, pure or mixed. {\Xi} is a measure which is universal, sensitive, monotonic, and unbounded. {\Xi}[{\rho}] yields a single positive value to quantify how nonclassical {\rho} is. {\Xi} employs phase space distributions to represent {\rho} and is a fixed function, {\Xi}[.], independent of the system, its environment or the type of state.

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Ole Steuernagel, Hsien-Yi Hsieh, Yi-Ru Chen, Ray-Kuang Lee. 2023-11-29. A Sensitive Quantumness Measure for One-Dimensional Continuous-Variable Systems. https://arxiv.org/abs/2311.17399

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