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Quantum nonlinear spectroscopy of single nuclear spins
Jonas Meinel1,2, Vadim Vorobyov1, Ping Wang3,4
13rd Institute of Physics, Research Center SCoPE and IQST, University of Stuttgart, 70569, Stuttgart, Germany.
Nature Communications
|September 9, 2022
Summary
Quantum nonlinear spectroscopy uses entangled quantum sensors to reveal all correlations within quantum systems. This method successfully measured fourth-order correlations in nuclear spins, offering new possibilities for quantum sensing and physics research.
Area of Science:
- Quantum Physics
- Quantum Sensing
- Spectroscopy
Background:
- Conventional nonlinear spectroscopy with classical probes has limitations in accessing complex correlations within quantum systems.
- Understanding higher-order correlations is crucial for advancing quantum technologies and fundamental physics research.
Purpose of the Study:
- To introduce and demonstrate quantum nonlinear spectroscopy for extracting arbitrary correlations in quantum systems.
- To showcase the capability of measuring fourth-order correlations, inaccessible by conventional methods.
Main Methods:
- Entangling a quantum sensor with a quantum object.
- Performing sequential weak measurements using a nitrogen-vacancy center in diamond.
- Measuring fourth-order correlations of single nuclear spins.
Main Results:
- Quantum nonlinear spectroscopy successfully extracted arbitrary types and orders of correlations.
- Fourth-order correlations of single nuclear spins were measured, surpassing conventional techniques.
- Distinct "fingerprint" features were identified for different quantum objects, enabling differentiation.
Conclusions:
- Quantum nonlinear spectroscopy offers a powerful new tool for probing quantum systems.
- This technique enables the study of higher-order correlations for applications in quantum sensing and fundamental physics.
- The findings pave the way for exploring quantum foundations and many-body physics.
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