Nonreciprocal waveguides and lenses based on the Fresnel-Fizeau effect

The propagation of a radiation beam in a medium whose velocity varies in the direction transverse to the axis of the beam is considered. It is shown that, under these conditions, the Fresnel-Fizeau effect of partial entrainment of light leads to focusing of the beam and to the possibility of the waveguide propagation of light. The corresponding waveguides and lenses have the property of nonreciprocity; i.e., their characteristics change with the reversal of the direction of propagation. The estimates obtained show the feasibility of observing the effect for optical radiation. (C) 2003 MAIK "Nauka/Interperiodica".