光在極低强度下的干涉现象

用Michelson干涉仪得出干涉图案;用光电倍增管计算光子率,由此测定该图案内的强度分布。证明了极低光强度下所得的图案与正常强度所得的图案,在实验误差范围内没有区别。在低光强度下,每秒钟约有10⁶光子进入干涉仪,因此,在这样的低光强度下,平均说来,在任何时间,干涉仪内具有的光子数还远不到一个。

THE INTERFERENCE PHENOMENA OF LIGHT AT VERY LOW INTENSITY

An interference pattern is obtained with a Michelson interferometer; the intensity distribution in the pattern is determined by counting the rate of photons by means of a photomultiplier. It is shown that the pattern obtained for very low intensities of light does not differ outside the margin of experimental error from the pattern obtained for normal intensities. At low intensities about 10⁶ photons enter the interferometer per second thus for these low intensities in average at any time much less than one photon is contained inside the interferometer.