溶液中の高速移動境界によるレ-ザ光のドップラ-効果 Doppler Effect of a Laser by a Fast Moving Boundary Liquid

The Doppler frequency shift of an optical wave can be made, not only by moving media, but by a moving boundary in a stationary medium. Especially, the reflected wave by the boundary is shifted by a large amount of the frequency, as the velocity of the boundary approaches the one of the light. The moving boundary in a stationary medium can be produced in a liquid, in nitro-benzene (C_6H_5NO_2) for example, by a high voltage pulse, transmitted along a strip line which is installed in a cell filled with the liquid. This paper describes, theoretically and experimentally, the Doppler frequency shift of a He-Ne laser by the moving boundary. The frequency of the light transmitted to the end of the cell is shifted by about 15MHz. The shifted frequency of the reflected light by the boundary has not, however, been observed yet, because the variation of the refractive index of the medium is too little. From the results of this paper the large amount of the frequency shift of the laser is highly expected if the medium with the large kerr constant is discovered in the near future.