2000 Fiscal Year Annual Research Report

多光子励起による半導体量子ドットの励起電子多体効果

Research Project

Project/Area Number	10304022
Research Institution	Osaka University
Principal Investigator	伊藤正大阪大学, 基礎工学研究科, 教授 (60004503)
Co-Investigator(Kenkyū-buntansha)	枝松圭一大阪大学, 基礎工学研究科, 助教授 (10193997) 石原一大阪大学, 基礎工学研究科, 助教授 (60273611) 張紀久夫大阪大学, 基礎工学研究科, 教授 (60013489)
Keywords	半導体量子ドット / 閉じ込め電子系 / 励起子多体効果 / オージェ過程 / 非線形感受率 / サイズ依存性 / 縮退4光波混合 / 単一量子ドット顕微分光
Research Abstract	1.(411)A面上に成長したGaAs量子ドットの単一量子ドット蛍光顕微分光により、1つのGaAs離散構造内に複数個のドットが存在すること、ある励起エネルギー以上では共通の連続準位を持つことを励起スペクトルの比較から同定した。励起子離散準位の直接励起によりアンチストークス側にオージェ多体効果によると見られる発光を見出した。CdSe/ZnSe量子ドットについても離散電子励起状態とその多体効果を確認した。 2.CuCl超微粒子のUV励起赤外過渡吸収の測定を行ない、励起子の励起状態吸収以外に、表面トラップ準位によると思われる長寿命の誘起吸収が存在すること、その励起強度依存性、回復時間の温度依存性から超微粒子の光イオン化と関連深いことを示した。 3.CaF_2単結晶の(111)へき開面上へのCuCl量子井戸・ドットのMBE成長を試みた。AFMで観察した成長のモルフォロジーは基板温度に大きく依存し、80℃では薄膜状で5-10nmの表面凹凸を持つが、180℃では3角形平板状のモザイク模様となり表面凹凸も1-1.5nmに減少し、220℃においては1.5-3nmの量子ドットに変化した。 4.一次元フレンケル励起子系において、長波長近似の範囲内で1励起子の最低共鳴準位における3次非線形感受率χ^<(3)>はサイズ比例増大を示すが、Pauli排他律のみでは1励起子状態のみと2励起子状態を経由する過程間の相殺効果により飽和する。今回、励起子間相互作用を考慮すると2励起子準位構造の変化とともに相殺の様子が変わり、χ^<(3)>が飽和するサイズや増大の傾きが大きく変化することを明らかにした。 5.従来我々(石原・張)が予言してきた非局所性が誘起する巨大非線形応答と思われる縮退四光波混合(DFWM)信号が最近GaAs薄膜で観測された。今回、これに関連する系統的実験データ(線形スペクトル、DFWMの層厚依存性)を詳細に理論解析し、予言通り、信号が非双極子的な空間構造を持つ内部電場の共鳴増大によるものであることを確認した。

Research Products

(16 results)

All Other

All Publications (16 results)

[Publications] K.Edamatsu: "Non-Markovian relaxation of excitons confined in CuCl quantum dots studied by resonant secondary emission"Phys.Stat.Sol.(a). 178. 317-321 (2000)
[Publications] K.Yamanaka: "Excited-state absorption of excitons confined in CuCl quantum dots"J.Lumin. 87-89. 312-314 (2000)
[Publications] K.Edamatsu: "Micro-photoluminescence spectroscopy of CuCl quantum dots in thin NaCl crystals"J.Lumin. 87-89. 387-389 (2000)
[Publications] T.Hirai: "Luminescence of colloidal CuI particles dispersed in KI matrix under matrix excitation-Energy transfer through the interface-"Proceedings of the Fourth Symposium on Atomic-scale Surface and Interface Dynamics. 165-170 (2000)
[Publications] K.Edamatsu: "Homogeneous linewidths of the resonant luminescence spectra of CuCl quantum dots"Quantum Electronics and Laser Science Conference 2000 Technical Digest. 87-88 (2000)
[Publications] C.Watatani: "Micro-photoluminescence of single GaAs/AlGaAs quantum dots grown on a (411) A GaAs surface"Quantum Electronics and Laser Science Conference 2000 Technical Digest. 57-58 (2000)
[Publications] B.P.Zhang: "Time-resolved photoluminescence of ZnCdSe single quantum dots"J.Cryst.Growth. 214/215. 765-769 (2000)
[Publications] K.Edamatsu: "Resonant luminescence linewidths and confined-phonon sidebands of CuCl quantum dots"Phys.Stat.Sol.(b). (in press).
[Publications] T.Itoh: "Photophysics of confined excitons in CuCl nanoparticles-Confinement of exciton excited states-"Proc.of the 2000 International Conference of Excitonic Processes in Condensed Matter. (in press). (2001)
[Publications] T.Hirai: "Excitons in colloidal CuI particles dispersed in a KI crystal"Proc.of the 2000 International Conference of Excitonic Processes in Condensed Matter. (in press). (2001)
[Publications] K.Yamanaka: "Photoinduced infrared absorption spectra of CuCl quantum dots in NaCl"Proc.of the 2000 International Conference of Excitonic Processes in Condensed Matter. (in press). (2001)
[Publications] T.Ota: "Investigation of carrier relaxation dynamics in single CdSe/ZnSe self-organized quantum dot by time-resolved micro-photoluminescence"Journal of Electronic Materials. (in press). (2001)
[Publications] A.Kawamori: "Growth of CuCl quantum wells and dots on CaF_2 (111) substrates by molecular beam epitaxy : Their morphology and optical spectra"Proceedings of the Fifth Symposium on Atomic-scale Surface and Interface Dynamics. (in press). (2001)
[Publications] H.Ishihara: "The Third Order Nonlinear Susceptibility of interacting one-dimentional Frenkel Excitons"Proc.Int.Conf.on Excitonic Processes in Condensed Matter, Osaka 2000, Int.J.Mod.Phys.B. (in press). (2001)
[Publications] H.Ishihara: "Resonant Size Enhancement of Degenerate Four Wave Mixing Signal of Weakly Confined Excitons"phys.stat.sol.(a). 221. 331-335 (2000)
[Publications] H.Ishihara: "Nonlocality induced size-enhancement of excitonic nonlinear response in high quality samples"Proc.25th Int.Conference on the Physics of Semiconductors (Osaka 2000),. (in press). (2001)

2000 Fiscal Year Annual Research Report

多光子励起による半導体量子ドットの励起電子多体効果

Principal Investigator

伊藤 正 大阪大学, 基礎工学研究科, 教授 (60004503)

Research Products

[Publications] K.Edamatsu: "Non-Markovian relaxation of excitons confined in CuCl quantum dots studied by resonant secondary emission"Phys.Stat.Sol.(a). 178. 317-321 (2000)

[Publications] K.Yamanaka: "Excited-state absorption of excitons confined in CuCl quantum dots"J.Lumin. 87-89. 312-314 (2000)

[Publications] K.Edamatsu: "Micro-photoluminescence spectroscopy of CuCl quantum dots in thin NaCl crystals"J.Lumin. 87-89. 387-389 (2000)

[Publications] T.Hirai: "Luminescence of colloidal CuI particles dispersed in KI matrix under matrix excitation-Energy transfer through the interface-"Proceedings of the Fourth Symposium on Atomic-scale Surface and Interface Dynamics. 165-170 (2000)

[Publications] K.Edamatsu: "Homogeneous linewidths of the resonant luminescence spectra of CuCl quantum dots"Quantum Electronics and Laser Science Conference 2000 Technical Digest. 87-88 (2000)

[Publications] C.Watatani: "Micro-photoluminescence of single GaAs/AlGaAs quantum dots grown on a (411) A GaAs surface"Quantum Electronics and Laser Science Conference 2000 Technical Digest. 57-58 (2000)

[Publications] B.P.Zhang: "Time-resolved photoluminescence of ZnCdSe single quantum dots"J.Cryst.Growth. 214/215. 765-769 (2000)

[Publications] K.Edamatsu: "Resonant luminescence linewidths and confined-phonon sidebands of CuCl quantum dots"Phys.Stat.Sol.(b). (in press).

[Publications] T.Itoh: "Photophysics of confined excitons in CuCl nanoparticles-Confinement of exciton excited states-"Proc.of the 2000 International Conference of Excitonic Processes in Condensed Matter. (in press). (2001)

[Publications] T.Hirai: "Excitons in colloidal CuI particles dispersed in a KI crystal"Proc.of the 2000 International Conference of Excitonic Processes in Condensed Matter. (in press). (2001)

[Publications] K.Yamanaka: "Photoinduced infrared absorption spectra of CuCl quantum dots in NaCl"Proc.of the 2000 International Conference of Excitonic Processes in Condensed Matter. (in press). (2001)

[Publications] T.Ota: "Investigation of carrier relaxation dynamics in single CdSe/ZnSe self-organized quantum dot by time-resolved micro-photoluminescence"Journal of Electronic Materials. (in press). (2001)

[Publications] A.Kawamori: "Growth of CuCl quantum wells and dots on CaF_2 (111) substrates by molecular beam epitaxy : Their morphology and optical spectra"Proceedings of the Fifth Symposium on Atomic-scale Surface and Interface Dynamics. (in press). (2001)

[Publications] H.Ishihara: "The Third Order Nonlinear Susceptibility of interacting one-dimentional Frenkel Excitons"Proc.Int.Conf.on Excitonic Processes in Condensed Matter, Osaka 2000, Int.J.Mod.Phys.B. (in press). (2001)

[Publications] H.Ishihara: "Resonant Size Enhancement of Degenerate Four Wave Mixing Signal of Weakly Confined Excitons"phys.stat.sol.(a). 221. 331-335 (2000)

[Publications] H.Ishihara: "Nonlocality induced size-enhancement of excitonic nonlinear response in high quality samples"Proc.25th Int.Conference on the Physics of Semiconductors (Osaka 2000),. (in press). (2001)

伊藤正大阪大学, 基礎工学研究科, 教授 (60004503)