Effect of excitation level on the optical properties of GaAs/AlGaO microdisks with an active region containing InAs quantum dots

Journal Article · Wed Oct 15 00:00:00 EDT 2008 · Semiconductors

DOI:https://doi.org/10.1134/S1063782608100151· OSTI ID:21255603

Blokhin, S A ^[1]; Sakharov, A V; Kulagina, M M; Zadiranov, Yu M; Gordeev, N Yu; Maksimov, M V ^[2]; Ustinov, V M ^[1]; Ledentsov, N N; Stock, E; Warming, T; Bimberg, D ^[3]

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1. Russian Academy of Sciences, St. Petersburg Physics and Technology Centre for Research and Education (Russian Federation)
2. Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation)
3. Technical University of Berlin, Institute for Solid State Physics (Germany)

The effect of the excitation level on the intensity and width of whispering-gallery-mode (WGM) lines in microdisks with an asymmetric air/GaAs/AlGaO waveguide and an active region containing InAs quantum dots is studied using microphotoluminescence spectroscopy. At high pump levels, overheating of the active region takes place, which leads to a long-wavelength shift of the gain spectrum; in addition, the shape of the spectrum changes due to the saturation of the ground and excited states and to many-particle interactions. As a consequence, the behavior of intensities and linewidths of WGMs as functions of the optical-pump power density is determined by the spectral positions of the modes with respect to the gain peaks and may differ considerably for different modes. The long-wavelength shift of WGM lines caused by active-region overheating is partially compensated by a short-wavelength shift, which occurs due to the dependence of the effective refractive index of the waveguide on the concentration of free charge carriers.

• OSTI ID: 21255603
• Journal Information: Semiconductors, Vol. 42, Issue 10; Other Information: DOI: 10.1134/S1063782608100151; Copyright (c) 2008 Pleiades Publishing, Ltd; Country of input: International Atomic Energy Agency (IAEA); ISSN 1063-7826
• Country of Publication: United States
• Language: English

Related Subjects

77 NANOSCIENCE AND NANOTECHNOLOGY
99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE
ALUMINIUM COMPOUNDS
CHARGE CARRIERS
EXCITATION
EXCITED STATES
GALLIUM ARSENIDES
INDIUM ARSENIDES
OXIDES
PARTICLE INTERACTIONS
PHOTOLUMINESCENCE
QUANTUM DOTS
REFRACTIVE INDEX
SPECTRA
SPECTROSCOPY
WAVEGUIDES
WAVELENGTHS