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Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection
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Simultaneous spin-charge relaxation in double quantum dots
V Srinivasa1, K C Nowack, M Shafiei
1Joint Quantum Institute, University of Maryland, College Park, Maryland 20742, USA. vsriniv@umd.edu
Physical Review Letters
|May 28, 2013
Summary
We explored how vibrations (phonons) affect electron spin relaxation in double quantum dots. Spin-orbit interaction via phonons is the main factor controlling this relaxation, which can be tuned with electrical signals.
Area of Science:
- Quantum physics
- Condensed matter physics
- Spintronics
Background:
- Electron spin relaxation is crucial for quantum computing.
- Understanding spin dynamics in quantum dots is essential for device development.
- Phonon-mediated interactions play a significant role in quantum systems.
Purpose of the Study:
- To investigate phonon-induced spin and charge relaxation mechanisms.
- To explore the role of spin-orbit and hyperfine interactions in electron spin relaxation.
- To understand the detuning dependence of spin relaxation in a double quantum dot.
Main Methods:
- Development of a toy model for phonon-induced relaxation.
- Experimental confirmation using a GaAs double quantum dot.
- Electrical tuning of spin relaxation rates.
Main Results:
- Spin relaxation rate shows non-monotonic dependence on detuning.
- Experimental results confirm the model's predictions.
- Relaxation rate is tunable over several orders of magnitude.
- Spin-orbit mediated relaxation via phonons is identified as the dominant mechanism.
Conclusions:
- Phonon-induced spin-orbit interaction is the primary driver of detuning-dependent spin relaxation.
- Electrical control of spin relaxation is demonstrated.
- The findings provide insights into controlling spin states in quantum dots.
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