Two-Photon Sepctroscopy on Excitons in Cu_2O with Developing a High Precision Spectroscopy Systen

Cu_2O中激子的双光子光谱研究及高精度光谱系统的开发

• 批准号: 08454077
• 负责人: HASUO Masahiro
• 金额: $ 0.51万
• 依托单位: KYOTO UNIVERSITY (1997)The University of Tokyo (1996)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08454077/
• 关键词: exciton; semiconductor; Cu_2O; Rydberg state; nonlinear optics; diamagnetic shift; photo conductivity; photo voltaic effect

Cu_2O is one of model materials in which Wannier exciton series are clearly observed. It has been found from high resolution spectroscopic studies sofar that exciton states of large principle quantum numbers(Rydberg exciton state)are stable in high quality Cu_2O crystals. One the other hand, ls-excitons in Cu_2O gather much notice due to the Bose-Einstein condensation(BEC)of excitons. The purpose of this work is to examine the Ryberg exciton states and the ls exciton state with developing a new spectroscopy system of high precision. Achievements of this work are as follows ;1.A high repetition(^-lkHz)frequency tunable IR laser excited by a CW Q-swiched YAG laser has been developed. A spectroscopy system of high resolution and high sensitivity has been also developed using a high resolution monochromator and a CCD camera.2.Diamagnetic shifts of 3[s-d]and 4[s-d]exciton doublet states have been measured to identifys and dexciton.3.Optical processes associated with the two-photon excitation of ls-ortho-excitons have been measured and discussed in view of the BEC of extions.4.Relaxation processes of ls-ortho-excitons have been examined from analyzes of emission spectra associated with the two-photon excitation of ls-ortho-excitons.5.A system to measure photo conductivity and photo-voltaic effects of Cu_2O at liquid helium temperature has been developed.6.Photo-voltaic effects of Cu_2O has been measured. One-and two-photon photo-voltaic spectroscopy has been demonstrated and its usefulness has been verified.

Cu_2O是清晰观察到万尼尔激子级数的模型材料之一。迄今为止，高分辨率光谱研究发现，高质量的Cu_2O晶体中大主量子数的激子态（里德伯激子态）是稳定的。另一方面，Cu_2O中的ls激子由于激子的玻色-爱因斯坦凝聚(BEC)而备受关注。这项工作的目的是通过开发一种新的高精度光谱系统来检查 Ryberg 激子态和 ls 激子态。本工作的主要成果如下： 1.研制了连续波调Q YAG激光器激发的高重频(^-lkHz)可调谐红外激光器。利用高分辨率单色仪和​​CCD相机开发了高分辨率和高灵敏度的光谱系统。2.测量了3[s-d]和4[s-d]激子双重态的抗磁位移以识别和分离激子。3.从BEC的角度测量并讨论了与ls-正激子双光子激发相关的光学过程。 4.通过分析ls-正激子双光子激发的发射光谱，研究了ls-正激子的弛豫过程。5.开发了液氦温度下测量Cu_2O光导率和光伏效应的系统。6.测量了Cu_2O的光伏效应。一光子和双光子光伏光谱已得到论证，其实用性已得到验证。

项目成果

M.Hasuo: "Study on Secondary Optical Processes by K-Selective Two-Photon Excitation of 1S-Ortho-Excitons in Cu_2O" Proceedings of XXIII International Conference of Physics of Semiconductor. 273-276 (1996)

M.Hasuo：“Cu_2O中1S-正激子的K选择性双光子激发的二次光学过程研究”第二十三届国际半导体物理会议论文集。

M.Hasuo: "Two-Photon Photo-Voltaic Spectroscopy on Wannier Excitons in Cu_2O" Fizika Tverdogo Tela (Sov.Phys.Solid State). (印刷中). (1998)

M.Hasuo：“Cu_2O 中万尼尔激子的双光子光伏光谱”Fizika Tverdogo Tela（Sov.Phys.Solid State）（出版中）。

M.Hasuo: "Study on Resonant Secondary Optical Processes by the Two-Photon Excitation of 1s-excitons in Cu_2O" Proceedings of the 2nd Asia Symposium on Condensed Matter Photophysics. 357-360 (1996)

M.Hasuo：“Cu_2O中1s激子双光子激发的共振二次光学过程研究”第二届亚洲凝聚态光物理学研讨会论文集。

M.Hasuo: ""Study on Resonant Secondary Optical Processes by the Two-Photon Excitation of ls-excitons in Cu_2O"" Proceedings of the 2nd Asia Symposium on Condensed Matter Photophysics. 357-360 (1996)

M.Hasuo：“Cu_2O中ls-激子双光子激发的共振二次光学过程研究”第二届亚洲凝聚态光物理学研讨会论文集。

M.Hasuo: ""Study on Secondary Optical Processes by K-Selective Two-Photon Excitation of lS-Ortho-Excitons in Cu_2O"" Proceedings of XXIII Intenational Conference of Physics of Semiconductor. 273-276 (1996)

M.Hasuo：“Cu_2O中1S-正激子的K选择性双光子激发的二次光学过程研究”第二十三届半导体物理国际会议论文集。