Abstract
Shubnikov-de Haas measurements between 0.06 and 1.6 K have been performed on two modulation-doped n-type Si/Si1-xGex heterostructures, and analysed to extract the quantum lifetime. Use of the conventional Dingle formula resulted in deviations from the expected theoretical behaviour above ∼0.3 K. The corresponding quantum lifetime appeared to increase with temperature in the same range. The data were then re-analysed using a modified expression, in which the thermal damping term was neglected. This gave plots with the correct characteristics, and a quantum lifetime which was approximately constant with temperature, as expected for ionized impurity scattering in a degenerate electron gas. A decrease in the quantum lifetime was observed above ∼1 K, and this is attributed to increased small-angle scattering due to acoustic phonons.
Original language | English (US) |
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Pages (from-to) | 1106-1110 |
Number of pages | 5 |
Journal | Semiconductor Science and Technology |
Volume | 13 |
Issue number | 10 |
DOIs | |
State | Published - Oct 1 1998 |
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering
- Materials Chemistry