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Updated: Jul 17, 2026

Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
RETRACTED: Real-time quantum feedback control of atomic spin-squeezing
J M Geremia1, John K Stockton, Hideo Mabuchi
1Physics and Control and Dynamical Systems, California Institute of Technology, Pasadena, CA 91125, USA. jgeremia@caltech.edu
Abstract:
Real-time feedback performed during a quantum nondemolition measurement of atomic spin-angular momentum allowed us to influence the quantum statistics of the measurement outcome. We showed that it is possible to harness measurement backaction as a form of actuation in quantum control, and thus we describe a valuable tool for quantum information science. Our feedback-mediated procedure generates spin-squeezing, for which the reduction in quantum uncertainty and resulting atomic entanglement are not conditioned on the measurement outcome.
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