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Related Experiment Video

Updated: Jul 17, 2025

Gradient Echo Quantum Memory in Warm Atomic Vapor

Gradient Echo Quantum Memory in Warm Atomic Vapor

Published on: November 11, 2013

Realizing spin squeezing with Rydberg interactions in an optical clock.

William J Eckner¹, Nelson Darkwah Oppong¹, Alec Cao¹

¹JILA, University of Colorado and National Institute of Standards and Technology, and Department of Physics, University of Colorado, Boulder, Colorado, USA.

|August 30, 2023

Summary

This summary is machine-generated.

Researchers created spin-squeezed entangled states in a neutral-atom optical clock, achieving significant metrological gain. This breakthrough enhances quantum metrology and atomic clock precision beyond the standard quantum limit.

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Area of Science:

Quantum physics
Quantum metrology
Atomic clocks

Background:

Neutral-atom arrays offer precise control for quantum physics studies.
These arrays are used in frequency metrology and studying entangled states.
Spin squeezing is a key operation for metrologically useful entanglement.

Purpose of the Study:

To realize spin squeezing in a programmable neutral-atom optical clock.
To leverage Rydberg-mediated interactions for quantum entanglement.
To enhance the precision of atomic clocks using quantum techniques.

Main Methods:

Utilizing neutral-atom arrays trapped in optical potentials.
Implementing Rydberg-mediated interactions for spin squeezing.
Performing synchronous frequency comparisons between independent squeezed states.

Main Results:

Achieved spin squeezing with nearly 4 decibels of metrological gain.
Observed fractional-frequency stability of 1.087(1) x 10^-15 at 1 second.
Reached a fractional precision at the 10^-17 level over 30 minutes, surpassing the standard quantum limit.

Conclusions:

Demonstrated a novel spin-squeezing protocol in a programmable atom-array clock.
This work enables quantum-information-inspired techniques for optimal phase estimation.
Paves the way for Heisenberg-limited optical atomic clocks.