Fabrication of a pump-probe terahertz emission microscope and investigation of ultrafast electronic devices

为了评价具有精细结构的光电器件，我们制作了一种结合原子力显微镜的近场激发激光太赫兹发射显微镜（LTEM）。在联合系统中，我们在激发飞秒脉冲激光的光路中引入了一种特殊的直径约为500 nm的窄孔径AFM悬臂，产生近场光来激发太赫兹波脉冲。利用该系统，我们成功地利用近场光激发低温生长GaAs （LT-GaAs）制成的领结天线产生了太赫兹波脉冲，并成功地同时观测了LTEM和AFM图像。另一方面，我们还通过优化在ht - gaas上制作的光导太赫兹探测器的天线结构，成功地实现了对太赫兹波脉冲的高灵敏度探测。

We have fabricated a near field excitation laser terahertz emission microscope (LTEM) combined with an atomic force microscope (AFM) in order to evaluate optoelectronic devices with fine structures. In the combined system we introduced a special AFM cantilever with a narrow aperture of about 500 nm into an optical path of excitation femtosecond pulsed laser to generate near-field light to excite terahertz wave pulses. Using the fabricated system, we have succeeded in the generation of terahertz wave pulse from a bowtie antenna fabricated on a low temperature grown GaAs (LT-GaAs) by near field light excitation, and also succeeded in the simultaneous observation of LTEM and AFM images.On the other hand, we have also succeeded in the high-sensitive detection of terahertz wave pulse by optimizing the antenna structure of photoconductive terahertz detector fabricated on LT-GaAs.