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Updated: Jun 19, 2026
11:21
Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
Switching mechanism in periodically driven quantum systems with dissipation.
Roland Ketzmerick1, Waltraut Wustmann
1Institut für Theoretische Physik, Technische Universität Dresden, 01062 Dresden, Germany.
Summary
We present a novel switching mechanism for quantum state occupations using periodic driving and heat bath coupling. This method efficiently controls quantum systems, even with weak driving, by exploiting avoided crossings.
Area of Science:
- Quantum Mechanics
- Statistical Physics
- Condensed Matter Physics
Background:
- Quantum systems are often influenced by external driving and environmental interactions.
- Understanding and controlling the dynamics of quantum states is crucial for quantum technologies.
- Avoided crossings in driven quantum systems offer unique opportunities for state manipulation.
Purpose of the Study:
- To introduce a general mechanism for switching asymptotic occupations of quantum states.
- To demonstrate the effectiveness of this mechanism under periodic driving and weak bath coupling.
- To illustrate the mechanism's application in controlling quantum potentials.
Main Methods:
- Analysis of quantum state occupations under combined periodic driving and weak coupling to a heat bath.
- Exploitation of avoided crossings in the system's Floquet spectrum.
- Numerical or analytical investigation of a specific asymmetric double-well potential model.
Main Results:
- A robust switching mechanism for quantum state occupations is introduced.
- The mechanism functions effectively even with weak driving and small occupations of involved Floquet states.
- The switching is independent of the initial state and driving duration.
- Demonstrated switching of an asymmetric double-well potential between wells using weak periodic driving.
Conclusions:
- The proposed mechanism offers a versatile method for controlling quantum state populations.
- This approach is applicable to various driven quantum systems interacting with an environment.
- Potential applications in quantum information processing and control of quantum systems.
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