Electro-optic field mapping system utilizing external gallium arsenide probes

External electro-optic probes fabricated from two different crystal orienta tions of GaAs have been implemented in an electro-optic sampling system tha t is capable of mapping three independent orthogonal components of free-spa ce electric fields. The results obtained for the radiated field from a micr ostrip patch antenna by the GaAs probes are compared with results on the sa me antenna obtained using bismuth silicate and lithium tantalate probes. An 8 mu m spatial resolution has also been demonstrated for the electro-optic field-mapping system, and the capability for the system to measure field p atterns at frequencies up to 100 GHz has been shown. (C) 2000 American Inst itute of Physics. [S0003- 6951(00)04529-0].