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Updated: Aug 27, 2025
11:21
Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
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Suppression of Interband Heating for Random Driving.
Hongzheng Zhao1,2, Johannes Knolle2,3,4, Roderich Moessner1
1Max-Planck-Institut für Physik komplexer Systeme, Nöthnitzer Straße 38, 01187 Dresden, Germany.
Physical Review Letters
|September 30, 2022
Summary
Controlling particle excitation in driven quantum systems is challenging. This study demonstrates that random multipolar drives can precisely control particle excitation, enabling observation of nonequilibrium phenomena in a long-lived prethermal state.
Area of Science:
- Quantum dynamics
- Non-equilibrium physics
- Condensed matter theory
Background:
- High-lying state excitation limits observing driven non-equilibrium phenomena.
- Broad spectrum drives exacerbate particle heating.
- Controlling quantum states under external drives is crucial.
Purpose of the Study:
- To investigate methods for controlling particle excitation in driven quantum systems.
- To explore the potential of structured random drives for mitigating heating.
- To enable observation of drive-induced phenomena in a stable regime.
Main Methods:
- Theoretical analysis of random multipolar drives.
- Investigating particle excitation dynamics in the lowest energy band.
- Exploring parameter regimes away from high-frequency driving.
Main Results:
- Particle excitation to higher bands is controllable with random multipolar drives.
- Heating can be suppressed even with broad spectrum drives.
- A long-lived prethermal regime in the lowest band is accessible.
Conclusions:
- Random multipolar drives offer a pathway to control quantum systems under non-equilibrium conditions.
- This control facilitates the experimental observation of drive-induced phenomena.
- The findings open new avenues for exploring quantum dynamics.
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