ESR investigations of modulation-doped Si/SiGe quantum wells

Authors
Jantsch, W Wilamowski, Z Sandersfeld, N Schaffler, F
Citation
W. Jantsch et al., ESR investigations of modulation-doped Si/SiGe quantum wells, PHYS ST S-B, 210(2), 1998, pp. 643-648
Citations number
12
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICA STATUS SOLIDI B-BASIC RESEARCH
ISSN journal
03701972 → ACNP
Volume
210
Issue
2
Year of publication
1998
Pages
643 - 648
Database
ISI
SICI code
0370-1972(199812)210:2<643:EIOMSQ>2.0.ZU;2-S
Abstract
In standard electron spin resonance (ESR) spectroscopy on modulation-doped SiGe/Si/SiGe quantum wells, we observe a very sharp ESR due to the 2d elect ron gas and also cyclotron resonance (CR) of free carriers in the well. Bot h signals increase persistently after illumination and the 2d CR becomes sh arper by one order of magnitude. We explain these effects together with the lack of Shubnikov-de Haas oscillations in terms of potential fluctuations due to the ionized donors which are partially neutralized and effectively s creened by photogenerated carriers.