为了研究锑化铟（ InSb）半导体材料光电导太赫兹辐射过程，用数值计算方法分析材料内载流子迁移率和表面电流，以及不同性质抽运激光器对太赫兹波近场强度的影响，用宏观电磁场理论和微观半导体理论分析材料表面电流，比较了InSb和GaAs材料的太赫兹波功率谱曲线。结果表明，InSb材料载流子弛豫时间越长，载流子迁移率越大；表面电流与载流子寿命和弛豫时间成正比；宏观电磁场理论更适于分析表面电流；抽运激光饱和能量密度越大，太赫兹近场辐射强度越强；抽运激光脉冲宽度越短，太赫兹近场辐射强度越强；InSb光电导辐射太赫兹波功率比GaAs高。该结果为基于InSb光电导太赫兹辐射源的研究奠定了一定的基础。%In order to study the photoconduction terahertz radiative process of InSb semiconductors , carrier migration rate and surface current were simulated .Effect of femtosecond pulse lasers with different properties on the near field terahertz ( THz) intensity was also analyzed .Surface current in the semiconductor material was analyzed with macroscopic electromagnetic theory and microscopic semiconductor theory respectively .Power spectrum curves of InSb and GaAs material were compared .The researches show that: the longer the InSb carrier auger relaxation time , the bigger the InSb carrier migration rate;the surface current is proportional to the carrier life and relaxation time;macroscopic electromagnetic theory is suitable for analyzing surface current;the bigger the saturated laser energy density , the stronger the near field THz intensity;the shorter the laser pulse width , the stronger the near field THz intensity; InSb material power is higher than GaAs material.The results lay a theoretical foundation for study on InSb photoconduction THz radiation .
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