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Quantum chaos and fluctuations in isolated nuclear-spin systems
1School of Physics, University of New South Wales, Sydney 2052, Australia.
Summary
We simulated quantum chaos in nuclear spin systems, finding magnetic noise spectra are identical for positive and negative temperatures. This has implications for experiments searching for fundamental symmetry violations.
Area of Science:
- Condensed matter physics
- Quantum mechanics
- Nuclear spin dynamics
Background:
- Recent interest in condensed-matter experiments for fundamental symmetry violation searches.
- Nuclear spins are cooled to microkelvin temperatures and isolated.
- Magnetic noise limits statistical sensitivity in these experiments.
Purpose of the Study:
- Investigate dynamical quantum chaos in isolated nuclear spin systems.
- Determine the structure of quantum states.
- Examine the validity of the Curie law for magnetic susceptibility.
- Characterize the magnetic noise spectrum.
Main Methods:
- Numerical simulations of isolated nuclear spin systems.
- Analysis of quantum state structures.
- Investigation of magnetic susceptibility.
- Calculation of magnetic noise spectra.
Main Results:
- Quantum chaos is investigated in isolated nuclear spin systems.
- The structure of quantum states is determined.
- The Curie law's validity for magnetic susceptibility is examined.
- The magnetic noise spectrum was found to be identical for both positive and negative temperatures.
Conclusions:
- The magnetic noise spectrum in isolated nuclear spin systems is independent of temperature sign.
- Understanding magnetic noise is crucial for improving sensitivity in symmetry violation experiments.
- Dynamical quantum chaos plays a role in the behavior of these systems.
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