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Updated: Jul 17, 2026
06:42
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
Science (New York, N.Y.)
|April 10, 2004
Summary
Real-time feedback during quantum nondemolition measurements influenced measurement outcomes. This quantum control method harnesses measurement backaction to generate spin-squeezing and atomic entanglement, valuable for quantum information science.
Area of Science:
- Quantum physics
- Atomic physics
- Quantum information science
Background:
- Quantum nondemolition measurements are crucial for preserving quantum states.
- Understanding and controlling measurement backaction is key for quantum technologies.
Purpose of the Study:
- To demonstrate real-time feedback during quantum nondemolition measurements.
- To show that measurement backaction can be harnessed for quantum control.
- To generate spin-squeezing and atomic entanglement independent of measurement outcomes.
Main Methods:
- Performing real-time feedback during quantum nondemolition measurements of atomic spin-angular momentum.
- Utilizing measurement backaction as a form of actuation in quantum control.
Main Results:
- Successfully influenced the quantum statistics of measurement outcomes.
- Demonstrated a feedback-mediated procedure to generate spin-squeezing.
- Achieved reduction in quantum uncertainty and atomic entanglement not conditioned on measurement outcomes.
Conclusions:
- Real-time feedback is a valuable tool for quantum control.
- Harnessing measurement backaction enables new quantum information science applications.
- The developed procedure offers a robust method for generating spin-squeezing and entanglement.
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