The complex dielectric constant epsilon(omega) of poled LiNbO3 crystals has
been measured from 90 to 147 GHz using a reflectometer bridge. Electric fi
eld polarizations in both the ordinary and extraordinary axes were studied.
The real part of epsilon(omega) differs only slightly from its value near
10 GHz, while the imaginary part is significantly larger than reported at l
ower frequencies. The data are used to model the dissipative losses of a go
ld co-planar waveguide on LiNbO3. (C) 2001 American Institute of Physics.