Abstract

Although organic polymers have been extensively used for second harmonic generation (SHG), the phase-matching between the fundamental and SH waves cannot essentially be satisfied to their bulk scheme as commonly done in inorganic crystals. Among various approaches to take the phase-matching the Cerenkov-radiative scheme is one of the promisings, in particular, suitable to organic polymers, of which the nonlinear optical(NLO) susceptibility χ⁽²⁾ is uniformly distributed over the guiding layer of a slab-guide. Then, the authors et al have firstly proposed to adopt a periodic or chirped periodic χ⁽²⁾ structure into the guiding layer even to the Cerenkovian scheme and have successfully demonstrated enhanced SHG power with an organic copolymer, i.e., VDCN/VAc film.^1,2 For enhancing conversion efficiency it is quite required not only to pursue an optimum geometrical structure onto the waveguide, but also to find an appropriate polymer having large NLO χ⁽²⁾ value including optical properties preferable to both fundamental and SH waves. In the present paper we shall experimentally apply the Cerenkov-radiative scheme with the periodic χ⁽²⁾ to a newly developed organic copolymer,³ i.e., vinylidene cyanide/P-hydroxy vinyl benzoate copolymer having 4-nitro-4’-oxo biphenyl chro­mophore (VDCN/VBZ-BPN) at a pulsed Nd:YAG 1.06 μm laser line as the fundamental wave.

© 1995 Optical Society of America