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Strategies for Real-Time Position Control of a Single Atom in Cavity QED

T. W. Lynn·K. Birnbaum·H. J. Kimble
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Abstract

Recent realizations of single-atom trapping and tracking in cavity QED open the door for feedback schemes which actively stabilize the motion of a single atom in real time. We present feedback algorithms for cooling the radial component of motion for a single atom trapped by strong coupling to single-photon fields in an optical cavity. Performance of various algorithms is studied through simulations of single-atom trajectories, with full dynamical and measurement noise included. Closed loop feedback algorithms compare favorably to open-loop "switching" analogs, demonstrating the importance of applying actual position information in real time. The high optical information rate in current experiments enables real-time tracking that approaches the standard quantum limit for broadband position measurements, suggesting that realistic active feedback schemes may reach a regime where measurement backaction appreciably alters the motional dynamics.

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T. W. Lynn, K. Birnbaum, H. J. Kimble. 2005-07-07. Strategies for Real-Time Position Control of a Single Atom in Cavity QED. https://doi.org/10.1088/1464-4266/7/10/004

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