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

本项目的目的是基于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发射器。阐明太赫兹辐射特性，并将太赫兹辐射应用于各个领域也是本项目的目的，取得了以下成果。通过对高温超导薄膜和天线结构的改进，在10 0 mW激励下，辐射功率达到10μW。这种辐射功率与半导体光开关的辐射功率竞争，因此实现了该项目的主要目的。通过对辐射特性的详细测量，提出了基于超快超流调制的辐射机制。提出并演示了激光激励太赫兹辐射的超流可视化。提出并验证了一种新的超导光磁囚禁存储器。利用连续多模激光二极管和光开关，研制了一种非常廉价的亚太赫兹光谱系统。我们制作了一套时间域太赫兹光谱系统，并将其应用于半导体的表征。

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.