光电效应实验中饱和光电流的影响因素探究  

The exploration of the influencing factors of saturated photocurrent in photoelectric effect

作　　者：刘丰宁 郑晓[1] 张国锋[1] 董国波[1] 徐平[1] LIU Feng-ning;ZHENG Xiao;ZHANG Guo-feng;DONG Guo-bo;XU Ping(School of Physics,Beihang University,Beijing 102206,China)

机构地区：[1]北京航空航天大学,物理学院,北京102206

出　　处：《大学物理》2025年第3期95-99,共5页College Physics

基　　金：北京航空航天大学校一流课程物理学(1)、电磁学资助;教育部高等学校大学物理课程教学指导委员会2023高等学校教学研究项目(DJZW202307hb)。

摘　　要：在光电效应实验中,饱和光电流的大小受到多种因素的影响,包括极板间的电压、入射光的频率、入射光强度和阴极材料的光电效率等.为了探究这些因素对饱和光电流的影响,我们采用了控制变量的实验方法,实验结果显示,在光电效率和频率一定的情况下,入射光强度与饱和光电流呈线性关系,直至达到饱和光电流.在入射光频率和光强一定的情况下,当极板间电压不足够大时,会影响到阴极材料的光电效率,从而影响饱和光电流的大小.在光强和电压一定的情况下,对于不同频率的光来说光子数必不相同,饱和光电流的大小是跟光子数直接相关的;此外,阴极材料的光电效率随着入射光的频率呈非线性变化,从而导致入射光的频率与饱和光电流之间存在非线性关系.综上所述,饱和光电流是一个特定条件下的极限值,是多个因素共同作用的结果.In the photoelectric effect experiment,the saturation photocurrent is affected by many factors,including the voltage between the plates,the frequency of the incident light,the intensity of the incident light and the photoelectric efficiency of the cathode material.In order to explore the influence of these factors on saturated photocurrent,we use the control variable experiment method.The experimental results show that the incident light intensity has a linear relationship with the saturation photocurrent until the saturation photocurrent is reached at a certain photoelectric efficiency and frequency.When the incident light frequency and light intensity are fixed,the photoelectric efficiency of the cathode material will be affected when the voltage between the plates is not large enough,and the saturation photocurrent will be affected.When the light intensity and voltage are fixed,the number of photons is different for different frequencies of light,and the saturation photocurrent is directly related to the number of photons.In addition,the photoelectric efficiency of the cathode material is nonlinear with the frequency of the incident light,resulting in a nonlinear relationship between the frequency of the incident light and the saturated photocurrent.To sum up,the saturated photocurrent is the limit value under a specific condition,which is the result of multiple factors.

关 键 词：光电效应 饱和光电流 光电效率 入射光强 入射光频率 

分 类 号：O413[理学—理论物理]