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High-Temperature and High-Pressure In situ Magic Angle Spinning Nuclear Magnetic Resonance Spectroscopy
Published on: October 9, 2020
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Spin noise spectroscopy beyond thermal equilibrium and linear response.
P Glasenapp1, N A Sinitsyn2, Luyi Yang3
1Experimentelle Physik 2, Technische Universität Dortmund, D-44221 Dortmund, Germany.
Physical Review Letters
|November 7, 2014
Summary
This study shows how weak radio frequency fields reveal spin fluctuation correlations beyond linear response. These methods uncover complex spin phenomena in alkali atom vapors, including multiphoton coherences.
Area of Science:
- Quantum Optics
- Atomic Physics
- Magnetic Resonance
Background:
- Linear response theory limits information from spin fluctuations in thermal equilibrium.
- Studying spin dynamics often requires polarized ensembles.
Purpose of the Study:
- To demonstrate that spin fluctuations, even in unpolarized ensembles, can reveal information beyond linear response.
- To explore the use of weak radio frequency fields to probe nonequilibrium and multiphoton spin phenomena.
Main Methods:
- Applying weak radio frequency magnetic fields to an unpolarized ensemble of (41)K alkali atoms.
- Analyzing intrinsic and random spin fluctuations to identify correlations and couplings.
Main Results:
- Observed Rabi splittings, Mollow triplets, and Autler-Townes doublets directly from spin fluctuations.
- Detected ac Zeeman shifts and nonlinear multiphoton coherences.
Conclusions:
- Weak RF fields enable the study of complex spin phenomena beyond linear response using unpolarized ensembles.
- Spin fluctuation analysis provides a powerful tool for investigating nonequilibrium and coherent spin dynamics.
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