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Measurement of Coherence Decay in GaMnAs Using Femtosecond Four-wave Mixing
Published on: December 3, 2013
Electric field-driven coherent spin reorientation of optically generated electron spin packets in InGaAs.
S Kuhlen1, K Schmalbuch, M Hagedorn
1II. Physikalisches Institut, RWTH Aachen University, 52056 Aachen, Germany.
Physical Review Letters
|October 23, 2012
Summary
Electric-field pulses enable precise control over electron spin orientations in InGaAs, achieving phase-coherent spin rotation. This breakthrough in semiconductor spintronics opens new avenues for advanced spin manipulation.
Area of Science:
- Semiconductor Spintronics
- Quantum Information Science
- Condensed Matter Physics
Background:
- Full electric-field control of spin orientations is crucial for advancing semiconductor spintronics.
- Existing methods often lack the precision for fine-tuned spin manipulation.
- Understanding spin dynamics in materials like InGaAs is key to developing new spintronic devices.
Purpose of the Study:
- To demonstrate the use of electric-field pulses for phase-coherent spin rotation in InGaAs.
- To explore the mechanism of electric-field-induced spin manipulation via spin-orbit interaction.
- To investigate spin dynamics through spin-echo experiments for potential applications in quantum computing.
Main Methods:
- Optically generated electron spin packets in InGaAs epilayers.
- Time-resolved Faraday rotation for detecting spin orientations.
- Application of precisely timed electric-field pulses to induce spin precession and rotation.
Main Results:
- Achieved phase-coherent ±π spin rotation of electron spins using electric-field pulses.
- Demonstrated that electric-field pulses effectively act as local magnetic field pulses via spin-orbit interaction.
- Observed a spin-echo effect with unexpected partial spin rephasing, doubling the spin dephasing time.
Conclusions:
- Electric-field pulses offer a powerful tool for arbitrary, two-dimensional spin orientation control in semiconductors.
- The findings pave the way for novel spintronic devices with enhanced control over electron spins.
- The observed spin-echo behavior suggests new possibilities for preserving spin coherence in quantum systems.
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