Abstract
We report on optical, photoreflectance and surface photovoltage, as well as terahertz photocurrent investigation of Be-doped GaAs/AlAs multiple quantum wells at room and liquid helium temperatures, respectively. From the Franz-Keldysh oscillations observed in photoreflectance spectra we determine built-in electric fields within the structure. Interband transition energies calculated by the transfer matrix method are in qualitative agreement with experimentally determined values for the samples having various, from 2 × 1010 up to 2.5 × 1012 cm-2, Be doping densities. The photocurrent observed in the range of 5.4-7.3 THz we associate with photoionization of Be-acceptor states.
| Original language | English |
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| Pages (from-to) | 328-332 |
| Number of pages | 5 |
| Journal | Acta Physica Polonica A |
| Volume | 107 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - 1 Feb 2005 |
| Externally published | Yes |
| Event | 12th International Symposium on Ultrafast Phenomena in Semiconductors - Vilnius, Lithuania Duration: 22 Aug 2004 → 25 Aug 2004 Conference number: 12 http://przyrbwn.icm.edu.pl/APP/SPIS/a107-1.html |