Spin polarization of neutral excitons in quantum dots: the role of the carrier collection area.
نویسندگان
چکیده
A high degree (approximately 55%) of circular polarization has been observed for the neutral exciton in InAs/GaAs quantum dots (QDs). The possibility to record non-zero polarization of the neutral exciton is explained in terms of different capture times of the light electron compared with the heavier holes into the QDs from the wetting layer. This interpretation is supported by the progressive reduction of the polarization degree with increasing QD density, and also with increasing temperature.
منابع مشابه
Wavelength and polarization variations of InAs/GaAs quantum dots emission at liquid Helium temperature via microphotoluminescence spectroscopy
In this paper, we investigate variation of the wavelength, intensity and polarization of the self-assembled InAs/GaAs quantum dots emission by microphotoluminescence spectroscopy at the liquid helium temperature. The microcavity wafer sample is grown by molecular beam epitaxy (MBE) and chemically etched into the micropillar structure (with elliptical cross section - long and short axis 2µm×1.5µ...
متن کاملWavelength and polarization variations of InAs/GaAs quantum dots emission at liquid Helium temperature via microphotoluminescence spectroscopy
In this paper, we investigate variation of the wavelength, intensity and polarization of the self-assembled InAs/GaAs quantum dots emission by microphotoluminescence spectroscopy at the liquid helium temperature. The microcavity wafer sample is grown by molecular beam epitaxy (MBE) and chemically etched into the micropillar structure (with elliptical cross section - long and short axis 2µm×1.5µ...
متن کاملShape - dependent exciton spin polarization studied by time - resolved magneto - optical spectroscopy
Submitted for the MAR10 Meeting of The American Physical Society Shape-dependent exciton spin polarization studied by timeresolved magneto-optical spectroscopy KENNETH KNAPPENBERGER, DANIEL BLUMLING, Florida State University — Shape-dependent exciton spin polarization of semiconducting nanoparticles will be presented. Timeand polarization-resolved magneto-photoluminescence spectroscopy is carri...
متن کاملTime-dependent analysis of carrier density and potential energy in spherical centered defect InGaAs/AlGaAs quantum dot (SCDQD)
Interaction and correlation effects in quantum dots play a fundamental role in defining both their equilibrium and transport properties. Numerical methods are commonly employed to study such systems. In this paper we investigate the numerical calculation of quantum transport of electrons in spherical centered defect InGaAs/AlGaAs quantum dot (SCDQD). The simulation is based on the imaginary time...
متن کاملSpin and energy transfer in nanocrystals without tunneling
We describe a mechanism of spin transfer between individual quantum dots without tunneling. Incident circularly polarized photons create interband excitons with nonzero electron spin in the first quantum dot. When the quantum-dot pair is properly designed, this excitation can be transferred to the neighboring dot via the Coulomb interaction with conservation or flipping of electron spin. The se...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Nanotechnology
دوره 21 34 شماره
صفحات -
تاریخ انتشار 2010