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Updated: Jun 25, 2026
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Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
Wigner-function nonclassicality as indicator of quantum chaos
A Kowalewska-Kudłaszyk1, J K Kalaga, W Leoński
1Nonlinear Optics Division, Institute of Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznań, Poland. annakow@amu.edu.pl
Summary
We introduce a new Wigner-function-based parameter to detect quantum chaos. This parameter measures the time evolution of nonclassicality in damped nonlinear oscillators, offering a novel indicator for quantum system behavior.
Area of Science:
- Quantum Optics
- Quantum Chaos Theory
- Nonlinear Dynamics
Background:
- Quantum chaos is a complex phenomenon in quantum systems.
- Nonclassicality quantifies deviations from classical behavior in quantum states.
- Wigner functions provide a phase-space representation of quantum states.
Purpose of the Study:
- To propose a novel Wigner-function-based parameter as an indicator of quantum chaos.
- To investigate the time evolution of nonclassicality in a specific quantum system.
- To establish a quantitative measure for quantum chaotic behavior.
Main Methods:
- Utilizing Wigner functions for quantum state representation.
- Defining a parameter based on the time dependence of nonclassicality.
- Analyzing a damped nonlinear (Kerr-like) oscillator model.
- Simulating the system's response to ultrashort external pulses.
Main Results:
- A new parameter, derived from the entropy of time-dependent nonclassicality, is proposed.
- This parameter serves as a sensitive indicator of quantum chaos.
- The study demonstrates the parameter's effectiveness in a damped nonlinear oscillator system.
Conclusions:
- The proposed Wigner-function-based parameter offers a robust method for identifying quantum chaos.
- The time evolution of nonclassicality is a key feature for detecting chaotic dynamics.
- This approach provides new insights into the quantum behavior of nonlinear systems.
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