Details
| Original language | English |
|---|---|
| Title of host publication | Spintronics V |
| Publication status | Published - 9 Oct 2012 |
| Event | Spintronics V - San Diego, CA, United States Duration: 12 Aug 2012 → 16 Aug 2012 |
Publication series
| Name | Proceedings of SPIE - The International Society for Optical Engineering |
|---|---|
| Volume | 8461 |
| ISSN (Print) | 0277-786X |
Abstract
Spin noise spectroscopy can be an extraordinary efficient, all-optical and low-perturbing tool to study the equilibrium spin dynamics in semiconductors. However, great care is necessary for studying the spin dynamics in inhomogeneous quantum dot ensembles. First, we show measurements on the spin dynamics of localized holes in (InGa)As quantum dots ensembles. The experiments reveal a very slow longitudinal spin relaxation time Tl and a moderately slow transverse spin relaxation time T2 * which results from the finite hyperfine interaction of the hole spins due to heavy-light hole mixing in (InGa)As quantum dots. The longitudinal spin relaxation rate shows a linear dependence on the probe intensity which suggests a linear extrapolation to zero intensity for the extraction of the intrinsic spin relaxation rate. However, calculations reveal that the intrinsic heavy-hole spin relaxation is easily shadowed in quantum dot ensembles by effects of finite absorption even if the majority of quantum dots is well out of resonance of the probe laser. For typical laser intensities and very long spin relaxation times, a linear extrapolation to zero intensity is therefore not allowed. What is more, the line shape of the spin noise spectra changes from Lorentzian to non-Lorentzian with increasing laser intensity which can be easily misinterpreted as an intrinsic non-exponential spin relaxation process.
Keywords
- Quantum dots, Quantum optics, Semiconductor, Spin dynamics, Spin noise spectroscopy
ASJC Scopus subject areas
- Materials Science(all)
- Electronic, Optical and Magnetic Materials
- Physics and Astronomy(all)
- Condensed Matter Physics
- Computer Science(all)
- Computer Science Applications
- Mathematics(all)
- Applied Mathematics
- Engineering(all)
- Electrical and Electronic Engineering
Cite this
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Spintronics V. 2012. 846105 (Proceedings of SPIE - The International Society for Optical Engineering; Vol. 8461).
Research output: Chapter in book/report/conference proceeding › Conference contribution › Research › peer review
}
TY - GEN
T1 - Spin noise spectroscopy
T2 - Spintronics V
AU - Oestreich, Michael
AU - Dahbashi, Ramin
AU - Berski, Fabian
AU - Hübner, Jens
PY - 2012/10/9
Y1 - 2012/10/9
N2 - Spin noise spectroscopy can be an extraordinary efficient, all-optical and low-perturbing tool to study the equilibrium spin dynamics in semiconductors. However, great care is necessary for studying the spin dynamics in inhomogeneous quantum dot ensembles. First, we show measurements on the spin dynamics of localized holes in (InGa)As quantum dots ensembles. The experiments reveal a very slow longitudinal spin relaxation time Tl and a moderately slow transverse spin relaxation time T2 * which results from the finite hyperfine interaction of the hole spins due to heavy-light hole mixing in (InGa)As quantum dots. The longitudinal spin relaxation rate shows a linear dependence on the probe intensity which suggests a linear extrapolation to zero intensity for the extraction of the intrinsic spin relaxation rate. However, calculations reveal that the intrinsic heavy-hole spin relaxation is easily shadowed in quantum dot ensembles by effects of finite absorption even if the majority of quantum dots is well out of resonance of the probe laser. For typical laser intensities and very long spin relaxation times, a linear extrapolation to zero intensity is therefore not allowed. What is more, the line shape of the spin noise spectra changes from Lorentzian to non-Lorentzian with increasing laser intensity which can be easily misinterpreted as an intrinsic non-exponential spin relaxation process.
AB - Spin noise spectroscopy can be an extraordinary efficient, all-optical and low-perturbing tool to study the equilibrium spin dynamics in semiconductors. However, great care is necessary for studying the spin dynamics in inhomogeneous quantum dot ensembles. First, we show measurements on the spin dynamics of localized holes in (InGa)As quantum dots ensembles. The experiments reveal a very slow longitudinal spin relaxation time Tl and a moderately slow transverse spin relaxation time T2 * which results from the finite hyperfine interaction of the hole spins due to heavy-light hole mixing in (InGa)As quantum dots. The longitudinal spin relaxation rate shows a linear dependence on the probe intensity which suggests a linear extrapolation to zero intensity for the extraction of the intrinsic spin relaxation rate. However, calculations reveal that the intrinsic heavy-hole spin relaxation is easily shadowed in quantum dot ensembles by effects of finite absorption even if the majority of quantum dots is well out of resonance of the probe laser. For typical laser intensities and very long spin relaxation times, a linear extrapolation to zero intensity is therefore not allowed. What is more, the line shape of the spin noise spectra changes from Lorentzian to non-Lorentzian with increasing laser intensity which can be easily misinterpreted as an intrinsic non-exponential spin relaxation process.
KW - Quantum dots
KW - Quantum optics
KW - Semiconductor
KW - Spin dynamics
KW - Spin noise spectroscopy
UR - http://www.scopus.com/inward/record.url?scp=84872111511&partnerID=8YFLogxK
U2 - 10.1117/12.930866
DO - 10.1117/12.930866
M3 - Conference contribution
AN - SCOPUS:84872111511
SN - 9780819491787
T3 - Proceedings of SPIE - The International Society for Optical Engineering
BT - Spintronics V
Y2 - 12 August 2012 through 16 August 2012
ER -