S. Baccaro et al., ORDINARY AND EXTRAORDINARY COMPLEX REFRACTIVE-INDEX OF THE LEAD TUNGSTATE (PBWO4) CRYSTAL, Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment, 385(2), 1997, pp. 209-214
The ordinary and the extraordinary complex refractive index of PbWO4 t
ogether with the crystal optical axis orientation are determined on th
e basis of transmittance and reflectance measurements at normal incide
nce with polarised light and the measurement of the separation angle b
etween the ordinary and the extraordinary ray at various laser wavelen
gths. The real part of the extraordinary complex refractive index is l
ower than the ordinary one (i.e. PbWO4 is a negative uniaxial crystal)
and they seem not to be affected by a 30 ppm Nb5+ doping.