Hidden resonant excitation of photoluminescence in bilayer arrays of InAsÕGaAs quantum dots
نویسندگان
چکیده
Photoluminescence ~PL! of self-organized quantum dots ~QDs! in bilayer InAs/GaAs structures is studied with a fixed seed layer and spacer, but variable second-layer coverage. Careful line shape analysis reveals modulation in the high-energy tail of the seed-layer PL spectrum. The oscillation-like behavior is reproducible with variations in both the temperature and optical excitation energy. These oscillations are attributed to carrier relaxation through inelastic phonon scattering from the wetting layer to the QD excited states. © 2003 American Institute of Physics. @DOI: 10.1063/1.1606109#
منابع مشابه
Photoluminescence up-conversion in InAsÕGaAs self-assembled quantum dots
We report up-converted photoluminescence in a structure with InAs quantum dots embedded in GaAs. An efficient emission from the GaAs barrier is observed with resonant excitation of both the dots and the wetting layer. The intensity of the up-converted luminescence is found to increase superlinearly with the excitation density. The results suggest that the observed effect is due to a two-step tw...
متن کاملSize selective photoluminescence excitation spectroscopy in CdTe quantum dots
We present a photoluminescence and photoluminescence excitation study of CdTe quantum dots, prepared via a novel organometallic approach. The global photoluminescence (excited at the energy above the absorption edge) showed a red shift of 75 meV with respect to the first absorption peak. This band edge emission was found to be strongly dependent on the excitation photon. Resonant emission spect...
متن کاملHigh temperature acidic oxidation of multiwalled Carbon nanotubes and synthesis of Graphene quantum dots
The acid oxidation of carbon nanotube generally results in opening the close ends of the nanotube and to make surface modifications. Herewith, Multiwall carbon nanotubes (MWCNTs) were oxidized in acids at high temperature experimental conditions which led to the formation of graphene quantum dots (GQDs). High resolution transmission electron microscope (HRTEM), energy dispersive X-ray spectro...
متن کاملHigh temperature acidic oxidation of multiwalled Carbon nanotubes and synthesis of Graphene quantum dots
The acid oxidation of carbon nanotube generally results in opening the close ends of the nanotube and to make surface modifications. Herewith, Multiwall carbon nanotubes (MWCNTs) were oxidized in acids at high temperature experimental conditions which led to the formation of graphene quantum dots (GQDs). High resolution transmission electron microscope (HRTEM), energy dispersive X-ray spectro...
متن کاملTemperature influence on optical charging of self-assembled InAsÕGaAs semiconductor quantum dots
It is demonstrated that the photoluminescence spectra of single self-assembled InAs/GaAs quantum dots are very sensitive to excitation energy and crystal temperature. This is qualitatively explained in terms of the effective diffusivity of photogenerated particles, which affects the capture probability of the quantum dot. As a consequence, this opens the possibility of controlling the average n...
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:
دوره شماره
صفحات -
تاریخ انتشار 2003