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Electrically detected electron spin resonance in a high-mobility silicon quantum well
Junya Matsunami1, Mitsuaki Ooya, Tohru Okamoto
1Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Physical Review Letters
|October 10, 2006
Summary
Investigating electron spin resonance (ESR) in a Si/SiGe heterostructure, this study found that reduced spin polarization, not electron heating, causes the ESR signal. This reveals a longitudinal spin relaxation time (T1) of approximately 1 ms.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Semiconductor Physics
Background:
- High-mobility two-dimensional electron systems (2DES) in Si/SiGe heterostructures are crucial for advanced electronic devices.
- Understanding electron spin dynamics is essential for spintronics and quantum computing applications.
Purpose of the Study:
- To investigate the origin of resistivity changes observed during electron spin resonance (ESR) absorption in a Si/SiGe 2DES.
- To determine the dominant mechanism responsible for the ESR signal and measure the longitudinal spin relaxation time (T1).
Main Methods:
- Utilized electron spin resonance (ESR) spectroscopy on a high-mobility 2DES in a Si/SiGe heterostructure.
- Analyzed resistivity changes under specific Landau level configurations and in-plane magnetic fields.
Main Results:
- Demonstrated that the ESR signal is primarily caused by a reduction in spin polarization, not electron heating.
- Measured a longitudinal spin relaxation time (T1) on the order of 1 ms at an in-plane magnetic field of 3.55 T.
- Observed that high-frequency spin precession suppresses Rashba fields, contributing to the extended T1.
Conclusions:
- The study clarifies the mechanism behind ESR-induced resistivity changes in Si/SiGe 2DES.
- The exceptionally long longitudinal spin relaxation time (T1) is attributed to the suppression of Rashba field effects by spin precession.
- Findings provide valuable insights for developing spintronic devices utilizing long spin lifetimes.
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