中文摘要：

低温条件下具有肖特基围栅结构的GaAs基单电子晶体管可重复探测到THz光子的光电流响应,实验表明，2．54THz的CH3OH气体激光垂直入射到单电子晶体管的量子点上，在随栅压变化的源漏共振电流峰附近，产生附加电流峰．通过这两个峰位的栅压间距可以估算出THz光子的能量．这表明附加电流峰是由THz光子辅助电子隧穿产生的．实验和理论都表明，单电子晶体管量子点尺寸的减小有利于THz光电流信号的增强.

英文摘要：

A reproducible terahertz （THz） photocurrent was observed at low temperatures in a Schottky wrap gate single electron transistor with a normal-incident of a CH3OH gas laser with the frequency 2.54THz. The change of source-drain current induced by THz photons shows that a satellite peak is generated beside the resonance peak. THz photon energy can be characterized by the difference of gate voltage positions between the resonance peak and satellite peak. This indicates that the satellite peak exactly results from the THz photon-assisted tunneling. Both experimental results and theoretical analysis show that a narrow spacing of double barriers is more effective for the enhancement of THz response.