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Updated: May 16, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Advantages of coherent feedback for cooling quantum oscillators
1Edward L. Ginzton Laboratory, Stanford University, Stanford, California 94305, USA. rhamerly@stanford.edu
Physical Review Letters
|December 11, 2012
Summary
Coherent feedback control enhances resonator cooling beyond standard methods. This optical feedback approach excels in quantum regimes, offering new pathways for advanced control systems.
Area of Science:
- Quantum optics
- Optomechanics
- Stochastic control theory
Background:
- Open optical and optomechanical resonators are crucial for quantum technologies.
- Cooling these resonators is essential for improving their performance.
- Current control methods have limitations, especially in the quantum regime.
Purpose of the Study:
- To model and analyze the cooling of resonators using optical feedback.
- To compare coherent feedback control with linear quadratic Gaussian (LQG) measurement-based schemes.
- To investigate the potential of coherent feedback for nonlinear and robust control.
Main Methods:
- Modeling resonator cooling within the linear quadratic Gaussian (LQG) framework.
- Utilizing stochastic control theory to analyze feedback mechanisms.
- Implementing all-optical feedback by embedding resonators in interferometers.
Main Results:
- Coherent feedback control schemes outperform optimal LQG measurement-based schemes in the quantum regime.
- Performance gains are observed at low steady-state excitation numbers.
- The ability to process noncommuting output field quadratures simultaneously is key to the observed gains.
Conclusions:
- Coherent feedback offers superior resonator cooling performance compared to LQG methods in specific quantum regimes.
- The fidelity of processing noncommuting quadratures is critical for the success of coherent feedback.
- Findings provide insights for designing advanced coherent feedback schemes for nonlinear and robust control applications.
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