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Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection
Published on: October 13, 2017
Directing nuclear spin flips in InAs quantum dots using detuned optical pulse trains.
S G Carter1, A Shabaev, Sophia E Economou
1Naval Research Laboratory, Washington, D.C. 20375-5322, USA.
Physical Review Letters
|June 13, 2009
Summary
Detuning optical pulses from quantum dot transitions precisely controls nuclear spin flip direction. This method enables stable control over nuclear spin polarization for advanced quantum technologies.
Area of Science:
- Quantum dots
- Spintronics
- Optics
Background:
- Nuclear spin polarization is crucial for quantum information processing.
- Controlling nuclear spin dynamics in quantum dots remains a challenge.
Purpose of the Study:
- To investigate the effect of detuned optical pulse trains on nuclear spin flips in quantum dots.
- To develop a method for controlling nuclear spin polarization direction.
Main Methods:
- Utilizing optical pulse trains detuned from electronic transitions in quantum dots.
- Applying an external magnetic field.
- Employing two-color, time-resolved Faraday rotation and ellipticity measurements.
Main Results:
- Detuned optical pulses generate electron spins with a component parallel to the magnetic field.
- This parallel spin component induces an asymmetry in nuclear spin flips.
- The direction of nuclear spin flips is controllable by optical pulse detuning.
Conclusions:
- Optical pulse detuning offers a novel pathway for directional control of nuclear spin flips.
- This technique provides a method for stabilizing and controlling nuclear spin polarization in quantum dots.
- The findings have implications for enhancing quantum memory and computation using quantum dots.
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