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Updated: May 9, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Decoherence, relaxation, and chaos in a kicked-spin ensemble
David Viennot1, Lucile Aubourg
1Institut UTINAM (CNRS UMR 6213, Université de Franche-Comté, Observatoire de Besançon), 41bis Avenue de l'Observatoire, BP1615, 25010 Besançon cedex, France.
Summary
We investigated quantum spin ensemble dynamics under ultrashort pulse control. Chaotic kick trains reveal a "horizon of coherence," a distinct signature preceding rapid quantum decoherence and population relaxation.
Area of Science:
- Quantum physics
- Nonlinear dynamics
- Spin systems
Background:
- Quantum spin ensembles are controlled by ultrashort pulse trains.
- Disturbances in pulse trains can follow regular, random, stochastic, or chaotic dynamics.
- Understanding decoherence and relaxation is crucial for quantum control.
Purpose of the Study:
- To model quantum decoherence and population relaxation in spin ensembles subjected to various kick train dynamics.
- To identify unique signatures of chaotic dynamics in quantum system evolution.
- To investigate the relationship between classical chaos and quantum decoherence.
Main Methods:
- Modeling spin ensemble dynamics using classical dynamical systems on a torus.
- Analyzing quantum decoherence and population relaxation.
- Relating decoherence/relaxation signatures to Lyapunov exponents of the underlying dynamical system.
Main Results:
- Quantum decoherence and population relaxation are induced by classical dynamical processes disturbing kick trains.
- Chaotic kick trains exhibit a distinct signature of chaos.
- This signature, termed 'horizon of coherence,' precedes rapid decoherence and relaxation.
Conclusions:
- Chaotic dynamics in kick trains leave a direct, measurable signature on quantum spin ensemble decoherence and relaxation.
- The 'horizon of coherence' provides a preliminary duration of stability before rapid quantum state decay.
- This finding links classical chaos to quantum phenomena, offering insights into quantum control and decoherence mechanisms.
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