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Scalable spin squeezing in a dipolar Rydberg atom array
Guillaume Bornet1, Gabriel Emperauger1, Cheng Chen2
1Charles Fabry Laboratory University of Paris-Saclay, Institute of Optics Graduate School, CNRS, Palaiseau Cedex, France.
Nature
|August 30, 2023
Summary
Researchers achieved scalable spin squeezing using short-range interactions in a quantum simulator. This method surpasses the standard quantum limit for enhanced measurement precision.
Area of Science:
- Quantum physics
- Quantum metrology
- Atomic physics
Background:
- The standard quantum limit (SQL) restricts measurement precision due to quantum fluctuations (quantum projection noise).
- Quantum metrology uses non-classical states to exceed the SQL, often employing spin squeezing.
- Traditional spin squeezing relies on all-to-all interactions, limiting scalability.
Purpose of the Study:
- To investigate if short-range interactions, specifically the 2D dipolar XY model, can achieve scalable spin squeezing.
- To demonstrate spin squeezing beyond the SQL using a Rydberg quantum simulator.
Main Methods:
- Utilized a dipolar Rydberg quantum simulator with up to 100 atoms.
- Employed quench dynamics from a polarized initial state.
- Implemented a multistep spin-squeezing protocol and Floquet engineering for Heisenberg interactions.
Main Results:
- Achieved spin squeezing that improved with system size, reaching -3.5 ± 0.3 dB (uncalibrated).
- Observed a calibrated squeezing of approximately -5 ± 0.3 dB.
- Enhanced squeezing by ~1 dB using a multistep protocol.
- Extended the lifetime of squeezed states via Floquet engineering.
Conclusions:
- Short-range interactions can realize scalable spin squeezing, challenging the necessity of all-to-all interactions.
- Rydberg quantum simulators provide a platform for generating and controlling spin-squeezed states.
- Advanced techniques like multistep protocols and Floquet engineering offer further improvements in squeezing and state lifetime.
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