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Published on: November 11, 2013
Classical diffusion of a quantum particle in a noisy environment
Ariel Amir1, Yoav Lahini, Hagai B Perets
1Faculty of Physics, Weizmann Institute of Science, Rehovot 76100, Israel.
Summary
Quantum wave packet spreading in noisy potentials exhibits classical diffusion due to decoherence. We analytically derive the diffusion coefficient, showing its dependence on noise and correlation time.
Area of Science:
- Quantum mechanics
- Condensed matter physics
- Statistical mechanics
Background:
- Quantum systems interacting with noisy environments undergo decoherence.
- Understanding the transition from quantum dynamics to classical behavior is crucial for various physical phenomena.
Purpose of the Study:
- To investigate the emergence of classical diffusion from quantum wave packet spreading in a tight-binding model with a noisy potential.
- To analytically determine the classical diffusion coefficient and its dependence on environmental noise characteristics.
Main Methods:
- Utilizing a separation of fast (dephasing) and slow (diffusion) processes.
- Analytical calculation of the diffusion coefficient for a noisy tight-binding model.
Main Results:
- Classical diffusive behavior emerges from quantum dynamics at long times.
- The classical diffusion coefficient is analytically derived and shown to depend on noise magnitude and correlation time.
Conclusions:
- Decoherence in noisy environments drives quantum systems towards classical diffusion.
- The developed method offers a general solution for analyzing quantum-classical transitions in diverse physical systems.
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