Ultrafast dynamics of type-II GaSb/GaAs quantum dots
- Centre for Advanced Photonics and Process Analysis, Cork Institute of Technology, Cork (Ireland)
- Department of Electrical Engineering and California NanoSystems Institute, University of California - Los Angeles, Los Angeles, California 90095 (United States)
- School of Science, Waterford Institute of Technology, Waterford (Ireland)
In this paper, room temperature two-colour pump-probe spectroscopy is employed to study ultrafast carrier dynamics in type-II GaSb/GaAs quantum dots. Our results demonstrate a strong dependency of carrier capture/escape processes on applied reverse bias voltage, probing wavelength and number of injected carriers. The extracted timescales as a function of both forward and reverse bias may provide important information for the design of efficient solar cells and quantum dot memories based on this material. The first few picoseconds of the dynamics reveal a complex behaviour with an interesting feature, which does not appear in devices based on type-I materials, and hence is linked to the unique carrier capture/escape processes possible in type-II structures.
- OSTI ID:
- 22415116
- Journal Information:
- Applied Physics Letters, Vol. 106, Issue 3; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
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