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Bayesian feedback control of a two-atom spin-state in an atom-cavity system
Stefan Brakhane1, Wolfgang Alt, Tobias Kampschulte
1Institut für Angewandte Physik der Universität Bonn, Wegelerstrasse 8, 53115 Bonn, Germany. brakhane@iap.uni-bonn.de
Physical Review Letters
|December 11, 2012
Summary
We demonstrate real-time feedback control for two neutral cesium atoms, stabilizing a unique quantum state. This method steers the system efficiently towards the target state, showing excellent agreement with simulations.
Area of Science:
- Quantum physics
- Atomic physics
- Quantum optics
Background:
- Controlling the quantum states of multiple atoms is crucial for quantum information processing.
- Optical cavities offer a way to interact with and measure atomic states.
Purpose of the Study:
- To experimentally demonstrate real-time feedback control of the joint spin-state of two neutral cesium atoms.
- To stabilize a deterministically inaccessible balanced two-atom mixed state.
Main Methods:
- Utilizing a high finesse optical cavity to confine two neutral cesium atoms.
- Discriminating quantum states based on cavity transmission levels.
- Employing a Bayesian update formalism for state estimation and feedback control.
Main Results:
- Successful real-time feedback control of the two-atom joint spin-state was achieved.
- The balanced two-atom mixed state was stabilized, which is deterministically inaccessible.
- Experimental results showed very good agreement with Monte Carlo simulations.
Conclusions:
- Real-time feedback control is effective for stabilizing complex multi-atom quantum states.
- The Bayesian update formalism provides accurate state estimation for feedback.
- This technique advances the ability to manipulate and control quantum systems for future applications.
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