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Anisotropy of the Velocity Space of Electromagnetic Radiation in a Moving Medium. Gladyshev V.O., Tiunov P.S., LeontТev A.D., Gladysheva T.M. and Sharandin E.A. // Technical Physics, 2012, Vol. 57, No. 11, pp. 1519Ц1528.

Anisotropy arising in moving media is considered. In these media, the phase velocity of light nonlinearly depends on the velocity vector field of the medium due to anisotropic binding forces between lattice atoms. Observations of the optical anisotropy of light in a rotating optically transparent medium are discussed. Laser radiation with wavelength ? λ = 0.632991 ± 1х10-7 μm propagating in an interferometer was passed through a rotating optical disk D = 62 mm in diameter. The projection of the beamТs path length in the medium onto the flat surface of the disk is l = 41 mm; the refractive index of the glass and its thickness are, respectively, n = 1.71250 for λ = 632.8 nm and 10 mm; and the angle of incidence of the beam on the flat surface of the disk is ϑ0 = 60?. The optical disk is rotated in two directions, and its rotation frequency may reach 250 Hz. Experimental data confirm the linear dependence of the fringe shift on the velocity of the medium up to 29.6 m/s. The measurement accuracy is sufficient to detect angular variations δΔ=3x10-5 in the position of fringes at a fixed rotation velocity of the optical disk.

Fig.1. Transverse light entrainment efficiency vs. refractive index n2 and angle of incidence ϑ0 = 90° - ϑ0'.

Fig.2. Total path length difference Δ+Σ vs. parameter r.

Fig.3. In the interferometer, a beam from laser L is divided by beam splitter BS2 into two beams propagating through the rotating optical disk in opposite directions. Because of rotation, one beam acquires a positive shift and the other negative.

Fig.4. Coordinate dependence of fringe intensity I(x) and (b) the time dependence of fringe intensity I(t) on the photodetector.

Fig.5. Spectrum of the initial interference signal.

Fig.6. Theoretical dependence of voltage U(ωt) applied to the photodetector on ωt for different values of xδ.

Fig.7. Estimated absolute error of Δt/T determination as a function of time.

Fig.8. Fringe shift ΔΣ measured over aperture of the photodetector as a function of rotation frequency ν for forward and backward rotations.

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