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Noisy Spins and the Richardson-Gaudin Model
Daniel A Rowlands1, Austen Lamacraft1
1TCM Group, Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom.
Physical Review Letters
|March 17, 2018
Summary
We found an exact solution for spin systems interacting with noisy environments. This method determines the decay rate, crucial for understanding quantum system stability.
Area of Science:
- Quantum Information Science
- Condensed Matter Physics
- Quantum Optics
Background:
- Studying spin systems (qubits) interacting with a shared noisy environment is essential for quantum technologies.
- Correlated noise can induce long-lived correlations in qubits, but relaxation is governed by frequency differences.
Purpose of the Study:
- To determine the exact decay rate of qubits coupled to a common noisy environment.
- To provide a method for evaluating the impact of frequency differences (inhomogeneous splittings) on qubit dynamics.
Main Methods:
- Mapping the spin system to a non-Hermitian integrable Richardson-Gaudin model.
- Calculating the exact spectrum of the quantum master equation in the high-temperature limit.
Main Results:
- Derived an exact solution for the decay rate of the quantum master equation.
- The solution accounts for correlated noise and differing spin precession frequencies.
Conclusions:
- The developed analytical solution accurately predicts the relaxation dynamics of coupled qubits.
- This framework is valuable for assessing the performance of quantum systems under realistic environmental conditions.
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