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Updated: Jul 11, 2026
09:23
Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
Universal phase shift and nonexponential decay of driven single-spin oscillations.
F H L Koppens1, D Klauser, W A Coish
1Kavli Institute of NanoScience Delft, P.O. Box 5046, 2600 GA Delft, The Netherlands.
Physical Review Letters
|October 13, 2007
Summary
We observed unusual power-law decay and phase shifts in driven Rabi oscillations of electron spins due to nuclear spin baths. This finding advances the use of electron spins as qubits.
Area of Science:
- Quantum physics
- Condensed matter physics
Background:
- Electron spins coupled to nuclear spin baths exhibit complex dynamics.
- Understanding these interactions is crucial for quantum information processing.
Purpose of the Study:
- To theoretically and experimentally investigate driven Rabi oscillations of a single electron spin.
- To explain the observed unusual features in the oscillations due to the nuclear spin bath.
Main Methods:
- Theoretical derivation of an expression for the coupled electron-nuclear system in the static limit.
- Experimental observation of driven Rabi oscillations.
Main Results:
- Observed power-law decay in oscillations, deviating from typical exponential decay.
- Identified a universal phase shift of approximately pi/4 in the oscillations.
- Theoretical model successfully explains these unusual phenomena.
Conclusions:
- The long correlation time of the nuclear spin bath significantly influences electron spin dynamics.
- The derived theoretical framework accurately describes the observed power-law decay and phase shift.
- This research provides critical insights for advancing electron spin-based quantum computing and qubit applications.
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