Abstract
The population and coherent dynamics of excitons in InAs quantum dots were investigated using transient pump-probe and four-wave mixing spectroscopies in the telecommunications wavelength range. The sample was fabricated on an InP(311)B substrate using strain compensation to control the emission wavelength. This technique also enabled us to stack over a hundred QD layers, which resulted in a significant enhancement of nonlinear signals. By controlling the polarization directions of incident pulses, we precisely estimated the radiative and non-radiative lifetimes, the transition dipole moment, and the dephasing time while taking into account their anisotropic properties. The measured radiative lifetime and dephasing time shows large anisotropies with respect to the crystal axes, which results from the anisotropic nature of the transition dipole moment. The anisotropy is larger than that for InAs quantum dots on a GaAs(100) substrate, which seems to reflect a lack of symmetry on an (311)B substrate. A quantitative comparison of these anisotropies demonstrates that non-radiative population relaxation and pure dephasing are quite small in our QDs.
| Original language | English |
|---|---|
| Title of host publication | Proceedings of SPIE - The International Society for Optical Engineering |
| Volume | 6779 |
| DOIs | |
| Publication status | Published - 2007 |
| Externally published | Yes |
| Event | Nanophotonics for Communication: Materials, Devices, and Systems IV - Boston, MA, United States Duration: 2007 Sep 10 → 2007 Sep 11 |
Other
| Other | Nanophotonics for Communication: Materials, Devices, and Systems IV |
|---|---|
| Country | United States |
| City | Boston, MA |
| Period | 07/9/10 → 07/9/11 |
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Keywords
- Quantum dot
- Strain compensation
- Transient nonlinear spectroscopy
ASJC Scopus subject areas
- Electrical and Electronic Engineering
- Condensed Matter Physics
Cite this
Strain-compensated quantum dots emitting at 1.5 micron : Resonant nonlinear optical properties and exciton dynamics. / Hayase, Junko; Akahane, Kouichi; Yamamoto, Naokatsu; Kujiraoka, Mamiko; Ema, Kazuhiro; Sasaki, Masahide.
Proceedings of SPIE - The International Society for Optical Engineering. Vol. 6779 2007. 677903.Research output: Chapter in Book/Report/Conference proceeding › Conference contribution
}
TY - GEN
T1 - Strain-compensated quantum dots emitting at 1.5 micron
T2 - Resonant nonlinear optical properties and exciton dynamics
AU - Hayase, Junko
AU - Akahane, Kouichi
AU - Yamamoto, Naokatsu
AU - Kujiraoka, Mamiko
AU - Ema, Kazuhiro
AU - Sasaki, Masahide
PY - 2007
Y1 - 2007
N2 - The population and coherent dynamics of excitons in InAs quantum dots were investigated using transient pump-probe and four-wave mixing spectroscopies in the telecommunications wavelength range. The sample was fabricated on an InP(311)B substrate using strain compensation to control the emission wavelength. This technique also enabled us to stack over a hundred QD layers, which resulted in a significant enhancement of nonlinear signals. By controlling the polarization directions of incident pulses, we precisely estimated the radiative and non-radiative lifetimes, the transition dipole moment, and the dephasing time while taking into account their anisotropic properties. The measured radiative lifetime and dephasing time shows large anisotropies with respect to the crystal axes, which results from the anisotropic nature of the transition dipole moment. The anisotropy is larger than that for InAs quantum dots on a GaAs(100) substrate, which seems to reflect a lack of symmetry on an (311)B substrate. A quantitative comparison of these anisotropies demonstrates that non-radiative population relaxation and pure dephasing are quite small in our QDs.
AB - The population and coherent dynamics of excitons in InAs quantum dots were investigated using transient pump-probe and four-wave mixing spectroscopies in the telecommunications wavelength range. The sample was fabricated on an InP(311)B substrate using strain compensation to control the emission wavelength. This technique also enabled us to stack over a hundred QD layers, which resulted in a significant enhancement of nonlinear signals. By controlling the polarization directions of incident pulses, we precisely estimated the radiative and non-radiative lifetimes, the transition dipole moment, and the dephasing time while taking into account their anisotropic properties. The measured radiative lifetime and dephasing time shows large anisotropies with respect to the crystal axes, which results from the anisotropic nature of the transition dipole moment. The anisotropy is larger than that for InAs quantum dots on a GaAs(100) substrate, which seems to reflect a lack of symmetry on an (311)B substrate. A quantitative comparison of these anisotropies demonstrates that non-radiative population relaxation and pure dephasing are quite small in our QDs.
KW - Quantum dot
KW - Strain compensation
KW - Transient nonlinear spectroscopy
UR - http://www.scopus.com/inward/record.url?scp=42549150340&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=42549150340&partnerID=8YFLogxK
U2 - 10.1117/12.732348
DO - 10.1117/12.732348
M3 - Conference contribution
AN - SCOPUS:42549150340
SN - 9780819469397
VL - 6779
BT - Proceedings of SPIE - The International Society for Optical Engineering
ER -