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Coherent manipulation of quantum delta-kicked dynamics: faster-than-classical anomalous diffusion
Jiangbin Gong1, Hans Jakob Wörner, Paul Brumer
1Chemical Physics Theory Group, Department of Chemistry, University of Toronto, Toronto, Canada M5S 3H6.
Summary
In a modified kicked rotor system, large regular islands transport energy in classical phase space. The quantum system shows faster energy absorption than classical anomalous diffusion, relevant to quantum chaos and control.
Area of Science:
- Quantum mechanics
- Classical mechanics
- Chaos theory
Background:
- The kicked rotor system is a standard model for studying classical and quantum chaos.
- Understanding energy transport in such systems is crucial for quantum control applications.
Purpose of the Study:
- To investigate the dynamics of a modified kicked rotor system with reversed kicking potential.
- To compare the energy absorption in the quantum system with classical anomalous diffusion.
Main Methods:
- Analysis of the classical phase space to identify regular islands.
- Numerical simulations of the quantum kicked rotor system over long time scales.
- Comparison of quantum energy absorption rates with classical diffusion rates.
Main Results:
- Observation of large, transporting regular islands in the classical phase space.
- Demonstration of significantly faster quantum energy absorption compared to classical anomalous diffusion.
- The enhanced energy absorption is observed across various system parameters and long time scales.
Conclusions:
- The modified kicked rotor system exhibits unique classical and quantum dynamics.
- Quantum effects can lead to anomalous energy absorption beyond classical predictions.
- These findings have implications for quantum chaos research and the development of quantum control strategies.
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