The polaronic nature of intraband relaxation in InAs/GaAs self-assembled quantum dots
- 作者：Zibik ; E.A. ; Wilson ; L.R. ; Green ; R.P. ; Bastard ; G. ; Ferreira ; R. ; Phillips ; P.J. ; Carder ; D.A. ; et. al.
- 关键词：78.67.Hc ; 78.47.+p ; 71.38.&minus ; k ; Quantum dots ; Polarons ; Intraband transitions ; Time-resolved spectroscopy
- 刊名：Physica E ; Low-dimensional Systems and Nanostructures
- 出版年：2005
- 期刊代码：139_13869477
- 类别：et
- 出版时间：February, 2005
- 卷：26
- 期：1-4
- 页码：408-412
- 文件大小：336 K
摘要
Polaron relaxation processes in a series of n-type InAs quantum dots (QDS) have been investigated using energy-dependent far-infrared pump–probe spectroscopy. For energies up to mg align=center border=0 SRC=/images/glyphs/BQ1.GIF>53meV, polarons decay to 2 longitudinal acoustic phonons; above this energy additional decay channels open resulting in a reduction of the decay time. Inter-state transfer has been observed between closely spaced p-like excited states, with the measured transfer times in good agreement with calculations assuming acoustic phonon assisted transfer. Finally, for QDs containing ≥2 electrons we observe evidence of a spin-flip process resulting in long (mg align=center border=0 SRC=/images/glyphs/BQ1.GIF>700ps) relaxation times.