Propagation of Electromagnetic Waves in Media Undergoing Complex Motions

Abstract

Results of a theoretical and experimental investigation into new effects in moving-media optics are presented. An exact analytical solution is obtained for the trajectory of the wave vector of a monochromatic electromagnetic plane wave in a medium undergoing a complex motion. It is shown that the spatial dragging of the electromagnetic wave by the moving medium can be described correctly in the general case only if relativistic terms of order β2 are taken into account. Also, in this investigation a spatial effect of the light drag was observed at a wavelength of λ =0· 63299 μm by means of an optical disk with a refractive index n=1· 4766, a radius of R0 =0· 06 m rotating at a frequency of ω =25 Hz. A relative shift of the interference pattern, monitored by the time of the interference band motion across the aperture of a photodetector for the disk rotating in the opposite directions, amounted to \(\Delta_\Sigma^{\rm exp} =0\cdot 0076\pm 0\cdot 0030\) of the interference bandwidth. The results of theoretical calculations of the expected interference pattern shift on the basis of the total solution of the dispersion equation in the experiment are in agreement with the experimental results. Analysis of the results obtained suggests that the detected effects determine a wide class of observed phenomena, even when the velocities of moving media are non-relativistic.