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06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Phase-space characterization of complexity in quantum many-body dynamics
Vinitha Balachandran1, Giuliano Benenti, Giulio Casati
1Department of Physics and Center for Computational Science and Engineering, National University of Singapore, Singapore 117542, Singapore.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|January 15, 2011
Summary
We introduce a new entropy measure for quantum complexity, applicable to various systems. It quantifies chaos and entanglement, aiding in detecting quantum phase transitions and distinguishing dynamics.
Area of Science:
- Quantum mechanics
- Statistical physics
- Complex systems
Background:
- Quantifying complexity in many-body quantum systems is challenging.
- Existing measures often do not fully capture both quantum entanglement and chaos.
- A unified measure is needed for diverse quantum states and systems.
Purpose of the Study:
- To propose a novel phase-space Wigner harmonics entropy measure for many-body quantum dynamical complexity.
- To develop a measure valid for both pure and mixed states in single-particle and many-body systems.
- To incorporate the interplay of chaos and entanglement in quantum dynamics.
Main Methods:
- Developed a phase-space Wigner harmonics entropy measure.
- Applied the measure to the Ising chain in a homogeneous tilted magnetic field.
- Analyzed multipartite entanglement generation and its effect on entropy.
Main Results:
- The proposed measure successfully quantifies quantum dynamical complexity.
- Multipartite entanglement leads to linear entropy increase until saturation in both integrable and chaotic regimes.
- Entropy growth rate effectively detects quantum phase transitions.
- The measure distinguishes integrable from chaotic dynamics by analyzing long-term fluctuations.
Conclusions:
- The Wigner harmonics entropy measure offers a robust tool for studying quantum complexity.
- It provides insights into the roles of entanglement and chaos in quantum dynamics.
- This measure has potential applications in detecting quantum phase transitions and characterizing quantum chaos.
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