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Updated: Jun 26, 2026
12:57
Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection
Published on: October 13, 2017
Intershell exchange and sequential electrically injected spin populations of InAs quantum-dot shell states
G Kioseoglou1, M Yasar, C H Li
1Naval Research Laboratory, Washington, District of Columbia 20375, USA.gnk@anvil.nrl.navy.mil
Physical Review Letters
|December 31, 2008
Summary
We controlled spin population in InAs quantum dots using spin-polarized current. We measured intershell exchange energies, revealing shifts in electroluminescence polarization due to intershell coupling.
Area of Science:
- Condensed matter physics
- Materials science
- Quantum optics
Background:
- Self-assembled InAs quantum dots are crucial for optoelectronic devices.
- Understanding electron shell occupation and interactions is key to device performance.
Purpose of the Study:
- To investigate sequential spin population in InAs quantum dot shells.
- To determine intershell exchange energies (s-p and p-d) using spin-polarized current.
- To analyze the influence of intershell exchange on electroluminescence (EL) spectra.
Main Methods:
- Utilized spin-polarized current from an Fe contact to control spin population.
- Resolved excitonic features in electroluminescence (EL) spectra.
- Analyzed circular polarization of EL spectra in relation to intensity peaks.
Main Results:
- Demonstrated sequential spin population of individual shell states.
- Observed shifts in EL circular polarization maxima relative to intensity peaks, attributed to intershell exchange.
- Quantified s-p intershell exchange energy as 7±2 meV and p-d intershell exchange energy as 13.5±1 meV.
Conclusions:
- Intershell exchange significantly impacts quantum dot electronic and optical properties.
- The findings provide crucial parameters for designing advanced quantum dot devices.
- This work advances the understanding of spin dynamics in low-dimensional semiconductor nanostructures.
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