ABSTRACT
Although both radio waves and light waves are electromagnetic waves, their
frequencies are very different. This is why in many substances the mutual
interaction between radio waves and light waves is essentially weak. At the
same time, there are (1) materials in which electrons and holes are generated
by optical transitions and (2) materials that exhibit electro-optic (EO), mag-
neto-optic (MO), or electroabsorption (EA) effects. In the former, the direc-
tion of interaction is from light waves to radio waves, whereas in the latter the
interaction is in the opposite direction. The latter group of effects can be
applied to a probe tip or sensor used in a measurement so that the radio wave
or electrical signal information is projected onto the light wave.