Development of high temperature superconductor terahertz emitter excited by ultrashort laser pulses

超短激光脉冲激发高温超导太赫兹发射器的研制

• 批准号: 08405028
• 负责人: HANGYO Masanori
• 金额: $ 23.23万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08405028/
• 关键词: high temperature superconductor; terahertz electromagnetic waves; ultrashort laser pulses; ultrafast optica response; supercurrent visalization system; superconducting optical flux trap memory; time domain terahertz spectroscopy; subterahertz wave

The aim of this project is to develop a highly efficient terahertz emitter made of high temperature superconductors based on the effect of terahertz radiation excited by femtosecond laser pulses. To clarify the radiation characteristics and to apply the terahertz radiation to various fields are also the purposes of the project The following results are obtained by the project.1. By the improvement of the high-Tc superconductor thin films and the antenna structure, the radiation power reached 10 μW with 100 mW excitation. This radiation power competes with that from the semiconductor photoswitches, and therefore the main purpose of the project is attained.2. By the detailed measurement of the characteristics of the radiation, we proposed the radiation mechanism based on the ultrafast supercurrent modulation.3. We proposed and demonstrated the supercurrent visualization by the laser excited terahertz radiation.4. A new superconducting optical magnetic flux trap memory is proposed and demonstrated.5. A very cheap subterahertz spectroscopic system using a CW multimode laser diode and photoswitch is developed.6. We made a time domain terahertz spectroscopic system and applied it to the characterization of semiconductors.

本项目的目的是利用飞秒激光脉冲激发的太赫兹辐射效应，研制一种由高温超导体制成的高效太赫兹辐射源。阐明太赫兹辐射的辐射特性，并将其应用于各个领域，也是本项目的目的.通过对高温超导薄膜和天线结构的改进，在100 mW激励下，辐射功率达到10 μW。该辐射功率与半导体光开关的辐射功率相竞争，从而达到了本项目的主要目的。通过对辐射特性的详细测量，提出了基于超快超电流调制的辐射机制.提出并实现了激光激发太赫兹辐射的超电流可视化.提出并实现了一种新型的超导光磁通阱存储器.研制了一种利用连续波多模半导体激光器和光电开关的亚太赫兹光谱系统.我们制作了一套时域太赫兹光谱系统，并将其应用于半导体材料的表征。

项目成果

M.Tonouchi: "Terahertz emission properties from flux-trapped YBCO thin films" Physica C. 293. 82-86 (1997)

M.Tonouchi：“通量捕获 YBCO 薄膜的太赫兹发射特性”Physica C. 293. 82-86 (1997)

M. Yamashita et al.: "Evaluation of supercurrent distribution by terahertz radiation mapping"Advances in Superconductivity. XI. 189-192 (1999)

M. Yamashita 等人：“通过太赫兹辐射映射评估超电流分布”超导进展。

M. Tonouchi: "Enhanced THz radiation from YBCO thin film bow-tie antennas with hyper-hemispherical MgO lens"IEEE Trans. on Appl Supercond.. 7. 2913-2916 (1997)

M. Tonouchi：“使用超半球形 MgO 透镜增强 YBCO 薄膜领结天线的太赫兹辐射”IEEE Trans。

S. Shikii: "Enhanced THz radiation from YBCO using a-Axis oriented thin films excited by ultrashort optical pulses"IEICE Trans.Commun.. E80-C. 1297-1303 (1997)

S. Shikii：“使用由超短光脉冲激发的 a 轴取向薄膜增强 YBCO 的太赫兹辐射”IEICE Trans.Commun.. E80-C。

M. Hangyo: "Terahertz radiation from YBCO thin films by optical pulse excitation"Advances in Superconductivity. X. 1205-1210 (1998)

M. Hangyo：“通过光脉冲激发从 YBCO 薄膜产生太赫兹辐射”超导进展。