| Autor: |
Hayes, D. G., Allford, C. P., Smith, G. V., McIndo, C., Hanks, L. A., Gilbertson, A. M., Cohen, L. F., Zhang, S., Clarke, E. M., Buckle, P. D. |
| Jazyk: |
angličtina |
| Rok vydání: |
2017 |
| Předmět: |
|
| ISSN: |
0268-1242 |
| Popis: |
We report magnetotransport measurements of InSb/Al1-xInxSb modulation doped quantum well structures and the extracted transport (τt) and quantum (τq) lifetime of carriers at low temperature (< 2 K). We consider conventional transport lifetimes over a range of samples with different doping levels and carrier densities, and deduce different transport regimes dependent on quantum well state filling calculated from self-consistent Schrödinger-Poisson modelling. For samples where only the lowest quantum well subband occupied at an electron densities of 2.13 x 1011 cm-2 and 2.54 x 1011 cm-2 quantum lifetimes of τq ≈ 0.107 ps, and τq ≈ 0.103 ps are extracted from Shubnikov-de Haas oscillations below a magnetic field of 0.8 T. The extracted ratio of transport to quantum lifetimes, τt/τq ≈ 17 and τt/τq ≈ 20 are similar to values reported in other binary quantum well two dimensional electron gas systems, but is inconsistent with predictions from a transport model which assumes that remote ionized donors are the dominant scattering mechanism. We find the low τt/τq ratio and the variation in transport mobility with carrier density cannot be explained by reasonable levels of background impurities or well width fluctuations. Thus, there is at least one additional scattering mechanism unaccounted for, most likely arising from structural defects. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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