MEASUREMENT OF NONLINEAR ABSORPTION AND REFRACTION IN TITANIUM-DIOXIDE SINGLE-CRYSTAL BY USING A PHASE-DISTORTION METHOD

Measurements of the nonlinear index of refraction (n2) and two-photon absorption coefficient (β) of titanium dioxide with rutile structure. The n2 and β were determined using the beam distortion method (Z-scan technique) with a Nd:YAG laser generating about 5 ns pulses at 532 nm. The β that was obtained was consistent with the results of earlier measurements, while the quantified n2 was greater that predicted theoretically by a factor of about 10. The deviation was justified by the applicable limit of a two-parabolic band model presumed in the theory.