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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
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Witnessing quantum chaos using observational entropy
Sreeram Pg1, Ranjan Modak2, S Aravinda2
1Department of Physics, Indian Institute of Science Education and Research, Pune 411008, India.
Physical Review. E
|July 19, 2023
Summary
Observation entropy (OE) quantifies chaos in quantum systems. It grows logarithmically in regular phases and faster in chaotic regimes, serving as a robust measure of quantum chaoticity.
Area of Science:
- Quantum mechanics
- Statistical physics
- Chaos theory
Background:
- The quantum kicked top model exhibits distinct classical phases: regular, mixed, and chaotic.
- Characterizing quantum chaos and its distinction from classical chaos is a key challenge.
Purpose of the Study:
- To investigate observation entropy (OE) as a measure of quantum chaoticity.
- To compare OE with out-of-time-ordered correlators (OTOC) in various quantum regimes.
- To differentiate between saddle-point scrambling and true chaos using OE.
Main Methods:
- Analysis of observation entropy (OE) in the quantum kicked top model.
- Comparison of OE dynamics with out-of-time-ordered correlators (OTOC).
- Investigation of OE's long-time behavior to distinguish scrambling from chaos.
Main Results:
- OE exhibits logarithmic growth with coarse-graining length in the regular phase and faster growth in the chaotic regime.
- The short-time growth rate of OE serves as a reliable indicator of system chaoticity.
- OE demonstrates greater robustness than OTOC in the deep quantum regime.
- Long-time OE analysis distinguishes persistent fluctuations of saddle-point scrambling from true chaos.
Conclusions:
- Observation entropy is a powerful tool for quantifying and understanding quantum chaos.
- OE provides a robust and insightful measure of chaotic dynamics in quantum systems.
- The study offers a new method for distinguishing quantum scrambling from true chaos.
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