用光电导天线产生太赫兹电磁波的饱和效应研究

根据半导体光电子学理论,分析了光注入非平衡载流子(电子-空穴对)的瞬态输运机理,研究了不同条件下的SI-GaAs光电导偶极天线太赫兹波辐射功率和辐射强度的饱和效应.结果表明其主要原因是在外加偏置电场作用下,光注入载流子出现了空间电荷电场屏蔽和辐射电场屏蔽现象,对提高太赫兹波辐射功率和辐射强度起到了遏制作用.对于电极间隙大小不同的天线,两种屏蔽效应的作用不同;在触发光能一定的情况下,照射光斑较大时屏蔽效应较小.

Research on Saturation Effect of THz Electromagnetic Wave Generated from Photoconductive Antenna

According to the theory of semiconductor optoelectronics, the transient transport mechanism of light-injected non-equilibrium carriers (electron-hole pairs) was analyzed, the saturation effect of THz wave radiation power and radiation intensity in SI-GaAs photoconductive dipole antenna under different conditions was studied. The main reason is that, under the action of DC bias electric field, the space charge electric field shielding and radiation electric field shielding will appear in optical injected carriers, thus the radiation power and intensity of THz wave are contained. The two shielding effects are different for antennas with different electrode gaps, the shielding effect is small when the light spot is large under the triggering light energy is certain.