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Updated: Apr 30, 2026
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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
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Exact nonadiabatic holonomic transformations of spin-orbit qubits.
T Čadež1, J H Jefferson2, A Ramšak3
1Jožef Stefan Institute, 1000 Ljubljana, Slovenia and Institute of Mathematics, Physics and Mechanics, 1000 Ljubljana, Slovenia.
Physical Review Letters
|May 3, 2014
Summary
Researchers derived an exact solution for electron spin dynamics in a moving quantum dot with time-dependent spin-orbit coupling. This allows arbitrary spin rotation on the Bloch sphere, with applications in quantum computing.
Area of Science:
- Quantum mechanics
- Condensed matter physics
- Spintronics
Background:
- Understanding electron spin dynamics is crucial for quantum technologies.
- Spin-orbit coupling in low-dimensional systems presents unique control opportunities.
Purpose of the Study:
- To derive an exact analytical solution for electron wave functions in a moving quantum dot.
- To investigate the effects of time-dependent spin-orbit coupling on electron spin.
- To explore methods for arbitrary spin rotation on the Bloch sphere.
Main Methods:
- Exact analytical solution of the Schrödinger equation.
- Analysis of cyclic evolutions in parameter space.
- Derivation of expressions for dynamical and geometrical phases.
Main Results:
- An exact solution for the electron wave function was obtained.
- Electron spin rotation is proportional to the area of a closed loop in parameter space.
- Arbitrary spin rotation angles on the Bloch sphere are achievable by parameter selection.
Conclusions:
- The study provides a theoretical framework for precise control of electron spin.
- The findings have implications for developing novel spintronic devices and quantum information processing.
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