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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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Quantum thermalization through entanglement in an isolated many-body system
Adam M Kaufman1, M Eric Tai1, Alexander Lukin1
1Department of Physics, Harvard University, Cambridge, MA 02138, USA.
Science (New York, N.Y.)
|August 20, 2016
Summary
Quantum entanglement drives the emergence of statistical mechanics in isolated quantum systems. Entanglement entropy locally mimics thermal entropy, validating statistical physics for observable properties.
Area of Science:
- Quantum physics
- Statistical mechanics
- Quantum information
Background:
- Isolated quantum systems in pure states exhibit zero entropy during unitary evolution.
- Statistical mechanics typically assumes thermal equilibrium and system entropy maximization.
- Reconciling quantum dynamics with thermodynamics is a fundamental challenge.
Purpose of the Study:
- To experimentally investigate the emergence of statistical mechanics from isolated quantum systems.
- To elucidate the role of quantum entanglement in this emergence process.
- To validate the application of statistical physics to local observables in quantum systems.
Main Methods:
- Utilizing advanced microscopy techniques to observe an evolving quantum system.
- Directly measuring entanglement entropy within the quantum state.
- Comparing experimental observations with theoretical predictions, including the eigenstate thermalization hypothesis.
Main Results:
- The overall quantum state of the system remained pure, contrary to classical entropy expectations.
- Local thermalization was observed, indicating emergent thermodynamic behavior.
- Entanglement entropy was found to directly correlate with and act as local thermal entropy.
Conclusions:
- Quantum entanglement is crucial for the emergence of statistical mechanics in isolated quantum systems.
- Entanglement entropy provides a quantum mechanical basis for local thermal entropy.
- Experimental findings support the eigenstate thermalization hypothesis and the validity of statistical physics for local observables.
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