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Updated: Jul 16, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Quantum dephasing and decay of classical correlation functions in chaotic systems
Valentin V Sokolov1, Giuliano Benenti, Giulio Casati
1Center for Nonlinear and Complex Systems, Università degli Studi dell'Insubria, Via Valleggio 11, 22100 Como, Italy.
Summary
This study introduces allegiance, a new measure of quantum interference, to quantify dephasing from internal chaotic motion. It connects quantum dephasing to classical correlations in semiclassical systems.
Area of Science:
- Quantum mechanics
- Quantum chaos
- Statistical physics
Background:
- Dephasing typically arises from environmental interactions.
- Understanding internal sources of dephasing is crucial for quantum systems.
- Quantum fidelity measures the distinguishability of quantum states.
Purpose of the Study:
- Introduce a new measure, allegiance, to quantify quantum interference.
- Investigate dephasing induced by internal classical chaotic motion.
- Connect quantum dephasing to classical dynamics in the semiclassical limit.
Main Methods:
- Extension of quantum fidelity for mixed states.
- Analytical derivation for a nonlinear driven oscillator.
- Numerical confirmation using the kicked rotor model.
Main Results:
- Allegiance quantifies quantum interference and is measurable via Ramsey interferometry.
- The decay of allegiance is directly linked to classical correlation functions in the semiclassical limit.
- Internal chaotic motion induces dephasing without external environments.
Conclusions:
- Allegiance provides a measurable tool to study dephasing from internal chaos.
- The study establishes a connection between quantum dephasing and classical correlations.
- Results are validated for both analytical and numerical models.
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