A HIGHLY EFFICIENT ORGANIC 2ND-ORDER NONLINEAR-OPTICAL CRYSTAL BASED AN A DONOR-ACCEPTOR-SUBSTITUTED 4-NITROPHENYLHYDRAZONE

We present a novel organic crystal, )-thiophenecarboxaldehyde-4-nitrop henyl-hydrazone, with a large effective phase-matchable nonlinear opti cal coefficient, d(eff)=29+/-3 pm/V at lambda = 1318 nm. Single crysta ls of dimensions up to 25x5X5 mm(3) were grown. The large off-diagonal nonlinear optical coefficients can be explained with the two-dimensio nal geometry of the chromophores in the crystal lattice. Our crystal i s ideally suited for optic parametric oscillation in the wavelength ra nge from 1000 to 2500 nm. (C) 1997 American Institute of Physics.