徳島大学 教育・研究者情報データベース(EDB)

1. 徳島大学.大学院社会産業理工学研究部.フロンティア研究センター.光ナノテクノロジー研究部門.ナノマテリアルテクノロジー分野(日亜寄附講座)(〜2018年3月31日)

1. 北田 貴弘([徳島大学.大学院社会産業理工学研究部.理工学域.ナノマテリアルテクノロジー(日亜)]/->個人[塚越 貴弘])

   役割	任意
   貢献度	任意
   学籍番号	推奨

2. (英) Ueyama Hyuga

   役割	任意
   貢献度	任意
   学籍番号	推奨

3. 森田 健

   役割	任意
   貢献度	任意
   学籍番号	推奨

4. 井須 俊郎

   役割	任意
   貢献度	任意
   学籍番号	推奨

(英) Ultrafast photocarrier relaxation processes in Er-doped InAs quantum dots embedded in strain-relaxed InGaAs barriers

(英) Time-resolved transmission change of Er-doped InAs quantum dots (QDs) embedded in strain-relaxedIn0.45Ga0.55As barriers has been studied using different excitation wavelengths (1.4-1.55μm) to understand the QD-size dependence of the photocarrier relaxation. Each measured temporal profilewas well reproduced by a sum of three exponential decays. Ultrafast (~1.6 ps) and fast (~ 6-9 ps)components are dominant in the initial stage of decay, and then the slow (~70-130 ps) componentdue to the radiative recombination in the QDs appears to be seen. The first two components come fromphotocarrier relaxation into the nonradiative centers related to Er dopants or the lattice relaxation. Thedifference is considered to result from whether the nonradiative centers are positioned inside oroutside the QDs. The decay time for the outside case becomes shorter as the excitation wavelength isshortened, which might be due to the weaker confinement of photocarriers in the smaller-size QDs.Suppression of the QDs contributing to the radiative recombination is also more significant for thesmaller-size QD excitation.