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Related Experiment Video

Updated: Jun 14, 2026

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Published on: June 8, 2018

Statistical approach to quantum chaotic ratchets.

¹Minerva Center and Department of Physics, Bar-Ilan University, Ramat-Gan 52900, Israel.

Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics

|April 7, 2010

Summary

Researchers studied the quantum ratchet effect in chaotic systems using phase-space uniform initial states. They found a zero-mean Gaussian current distribution, indicating a strong, experimentally observable effect.

Area of Science:

Quantum mechanics
Statistical physics
Chaos theory

Background:

The quantum ratchet effect describes directed motion in systems lacking symmetry.
Understanding this effect in fully chaotic systems requires analyzing statistical properties of currents.
Semiclassical initial states, phase-space uniform with Planck cell resolution, are crucial for analysis.

Purpose of the Study:

To investigate the quantum ratchet effect in fully chaotic systems.
To analyze the statistical properties of the ratchet current using specific initial states.
To predict and verify the nature of the current distribution.

Main Methods:

Studying statistical properties of the ratchet current.
Utilizing phase-space uniform initial states with maximal Planck cell resolution.

Related Experiment Videos

Last Updated: Jun 14, 2026

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Published on: June 8, 2018

Applying theoretical arguments for quantum-resonance values of a scaled Planck constant.

Main Results:

The distribution of the ratchet current follows a zero-mean Gaussian.
The variance of the current distribution is approximately Dħ²/ (2(2π)²), where D is the chaotic-diffusion coefficient.
The observed effect strength is significantly larger than for usual momentum states.

Conclusions:

The quantum ratchet effect in chaotic systems exhibits a predictable Gaussian current distribution.
The effect's strength, derived from specific initial states, is substantial.
These strong quantum ratchet effects are predicted to be experimentally observable.