| Autor: |
Y. Tanaka, Kenzo Fujiwara, Akihiro Satake, T. Tanigawa |
| Rok vydání: |
2010 |
| Předmět: |
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| Zdroj: |
Physica E: Low-dimensional Systems and Nanostructures. 42:2665-2668 |
| ISSN: |
1386-9477 |
| DOI: |
10.1016/j.physe.2010.02.009 |
| Popis: |
Thermal escape process of carriers has been investigated by steady-state and time-resolved photoluminescence (PL) spectroscopy in GaAs single-quantum-well (SQW) contained in GaAs/AlAs short-period superlattices (SPSs) over a wide temperature (T) range between 15 and 300 K. A typical PL spectrum indicates two emission bands corresponding to SQW and SPS layers. When the sample temperature is increased from 15 K, the PL intensity of SQW increases and reaches the maximum value at 50 K, while the PL intensity of SPS drastically decreases below 60 K. With further increase in temperature up to 120 K, the PL intensity of SPS increases. These results indicate the following processes: in the region of 15 < T < 50 K, the photogenerated carriers in the SPS layer can quickly relax into the SQW before radiative recombination within the SPS layer, as long as the vertical carriers transport assisted by phonon scattering is sufficient. In the region of 60 < T < 120 K, the carriers in the SQW can easily escape toward the SPS layer due to thermal excitation. These processes are supported by the time-resolved PL results where the escape time from the SQW to the SPS layers gets short with increase in temperature. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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