"A Series of Experimental Studies on Phase Transitions, Photo-Disclosed Ordered States, Dynamics of Superconductive-Conjugate Optical Phenomena in Oxide Systems"

“氧化物系统中相变、照片揭示的有序态、超导共轭光学现象动力学的一系列实验研究”

• 批准号: 06402023
• 负责人: MASUMI Taizo
• 金额: $ 18.82万
• 依托单位: GUNMA UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-06402023/
• 关键词: Oxides Insulators; Phase transitions; Photoconductivity with anomalies; Superconductive-conjugate characters; Superconductive optoelectronic devices; 光誘起秩序状態

1.Refining by Floating Zone Technique and Evaluation of Oxide Materials ; High-purity specimens of Cu_2O and CuO have been studied as the basic substances towards the Cu-O network in the Cuprate superconductive Oxides by spectrochemical analysis, X-ray diffraction, optical absorption, photoluminescence, and Raman scattering. These results revealed remakably new results both on Cu_2O and especially on CuO.2.A Trial Study of Phase Transition in Insulating Oxides by using the Anomalous Compton Scattering ; We have tried to pursue a potential existence of phase transitions of the valence electronic system in Cu_2O via studying the temperature dependence (T=15-300K) of the momentum distribution and spin polarization in the anomalous Compton scattering. Unfortunately, clear results have not been obtained because of lack of machine time available in the Synchrotron Oribit Radiation (SOR) Facilities in the High Energy Physics Laboratory (KEK).3.Studies of the Correlation between Phase Transiti … More ons and Occurrences of Anomalies in Photoconductivity ; With a wider view than ever, we extended our studies on the correlation between phase transitions and occurrences of anomalies in photoconductivity by studying the temperature dependence of pulsed photoconductivity in various substance, especially unexpectedly emerging photosignals with decreasing temperature in details, at wider electric and magnetic fields, wavelength and intensity of photoexcitation. Particularly, besides Cu_2O,we have extended studies to cover CuO,Sm_2CuO_4, etc.and obtained results remarkably similar to those in Cu_2O.We are approaching the Cu-O based superconductors by photodoping.4.Nonlinear Photomagnetism-Optical-Microwave Cyclotrone Double Resonance ; We have investigated intensively the nonlinear optical-microwave double cyclotron resonance of Cu_2O due to polarons with excitons in details. Besides, on the problem of an existence of the mid-gap states in Cu_2O,we newly studied the temperature dependence of microwave photoconductivity signals between T=4.2K and 300K similar to pulsed photoconductivity signals in a view of dynamical aspects of photoresponses at 35GHz. We have observed a resonant enhancement of microwave photoconductivity at lambda=614nm and around T=60K.5.Search for Superconductive-Conjugate Photoconductive Substance and Dynamics of Photoresponses ; We have examined the optical absorption, photoconductivity, photoluminescence of single or polycrystals and thin film of CuO,Sm_2CuO_4, etc.. and newly confirmed that CuO and Sm_2CuO_4 exhibit superconductive-conjugate photoconductivity. We have also studied the optical absorption of Ba_<1-x>K_xBiO_3 and light-irradiated effect on reduced Y-Ba_2-Cu_3-O_<7-delta>.6.Basic Studies of Superconductive Optoelectronic Devices ; By adopting a combination of the Cu-O based high-Tc Superconductor pairs and the insulator Cu_2O of superconductive-conjugate photoconductivity, we have pursued a possibility to build a superconductive optoelectronic device and of their application. In a basic aspect, we discovered a resonant shift of temperature dependence of photoconductivity of Cu_2O at the gate region with the occurrence of superconductive transitions of the Y-Ba-Cu-O,La-Sr-Cu-O,or La-Ba-Cu-O at the source and drain regions. In an aspect for applications, we confirmed a possibility of basic operation as a photo-transistor including three terminal FET-like arrangements. These results reveal a possibility to develop an integrated array of photoelectric devices at high density and high speed operations. Less

1.浮区法精炼及氧化物材料的评价用光谱化学分析、X射线衍射、光吸收、光致发光和拉曼散射等方法研究了铜氧化物中Cu-O网络的基本物质Cu_2O和CuO的高纯样品。这些结果揭示了Cu_2O，特别是CuO的一些新的结果。2.用反常康普顿散射研究绝缘氧化物中的相变我们试图通过研究反常康普顿散射中动量分布和自旋极化的温度依赖性（T=15- 300 K）来探讨Cu_2O中价电子系统相变的可能存在。遗憾的是，由于高能物理实验室（KEK）的同步辐射轨道辐射（SOR）装置缺乏可用的机器时间，还没有得到明确的结果。3.相变与温度的相关性研究 ...更多信息 光电导中的反常现象及其发生我们以更广阔的视野，通过研究各种物质的脉冲光电导的温度依赖性，特别是在更宽的电场、磁场、光激发波长和强度下，意外出现的光电信号随温度的变化，扩展了我们对光电导中相变与反常现象发生之间的相关性的研究。特别地，除了Cu_2O外，我们还将研究范围扩大到CuO、Sm_2CuO_4等，得到了与Cu_2O非常相似的结果。我们正在通过光掺杂来研究Cu-O基超导体。4.非线性光磁-光-微波双回旋共振：我们详细研究了Cu_2O的极化子与激子的非线性光-微波双回旋共振。此外，在Cu_2O中存在中间带隙态的问题上，我们从35 GHz光响应动力学的角度出发，研究了T=4.2K至300 K之间微波光电导信号与温度的关系，类似于脉冲光电导信号。在λ = 614 nm和T= 60 K附近观察到微波光电导的共振增强。5.超导-共轭光电导物质的寻找和光响应动力学研究了CuO、Sm_2CuO_4等单晶、多晶和薄膜的光吸收、光电导、光致发光等性质。新证实了CuO和Sm_2CuO_4具有超导共轭光电导。我们还研究了Ba_ K_xBiO_3的光吸收<1-x>和还原Y-Ba_2-Cu_3-O_3的光辐照效应<7-delta>。6.超导光电子器件的基础研究采用Cu-O基高温超导体对和超导共轭光电导的绝缘体Cu_2O相结合，探索了建立超导光电子器件的可能性及其应用。在一个基本的方面，我们发现了Cu_2O在栅区的光电导随温度变化的共振位移，并在源、漏区出现了Y-Ba-Cu-O、La-Sr-Cu-O或La-Ba-Cu-O的双稳跃迁。在应用方面，我们确认了作为包括三端FET样布置的光电晶体管的基本操作的可能性。这些结果揭示了开发高密度和高速操作的集成光电器件阵列的可能性。少

项目成果

Taizo Masumi and Masakatsu Isobe: ""Novel Concepts of Superconductive Optoelectronic Devices : Resonances of Photoconductivity in the Cu_2O Gate Region "(Invited)" Proc.SPIE-The International Society for Optical Engineering,Oxide Superconductor Physics an

Taizo Masumi 和 Masakatsu Isobe：“超导光电器件的新概念：Cu_2O 栅极区域光电导的共振”（特邀）Proc.SPIE-国际光学工程学会、氧化物超导物理学会

H.Minami: "" Optical Absorption Spectra of BaBiO_3 in Wide Temperature Range "" Physica C. 235-240. 1151-1152 (1994)

H.Minami：“宽温度范围内 BaBiO_3 的光学吸收光谱”Physica C. 235-240。

H.Minami and H.Uwe: ""SIS Structure of Ba_<1-x>K_xBiO_3 Fabricated by an Electrochemical Method"" Proc.9th Int.Symp.Superconductiveity,Sapporo Advances in Superconductivity IX. (1996,1997)

H.Minami 和 H.Uwe：“电化学方法制备的 Ba_<1-x>K_xBiO_3 的 SIS 结构””Proc.9th Int.Symp.Superconductiveity，札幌超导进展 IX。

H.Yamaguchi,S.Kagoshima,T.Masumi,J.Li,K.Kitazawa: ""Pulsed Photoconductivity in Single Crystals of C_<60> with Anomalies at Phase Transitions"" Proc.22nd Int.Conf.Phys.Semiconductors,. 3. 2097-2100 (1994)

H.Yamaguchi、S.Kagoshima、T.Masumi、J.Li、K.Kitazawa：““C_<60> 单晶中的脉冲光电导性与相变异常”Proc.22nd Int.Conf.Phys.Semiconductors，

P.K.Lawson, J.E.McCarthy, M.J.Cooper, E.Zukowski, D.N.Timms, F.Itoh, H.Sakurai, Y.Tanaka, H.Kawata, and M.Ito: ""Temperature Dependence of the Magnetic Compton Profile of Ferrimagnetic DyFe_2 and ErFe_2"" J.Phys. : Condens. Matter. Vol.7. 389-400 (1995)

P.K.Lawson、J.E.McCarthy、M.J.Cooper、E.Zukowski、D.N.Timms、F.Itoh、H.Sakurai、Y.Tanaka、H.Kawata 和 M.Ito：“亚铁磁性 DyFe_2 和磁性康普顿剖面的温度依赖性”