2ND-ORDER NONLINEARITY OF NONPOLED POLYMERIC THIN-FILMS DOPED WITH PYRYLIUM-SALTS WITH BLUE WINDOW CHARACTERISTICS

A novel nonlinear organic ionic material, or pyrylium salt dye, is syn thesized and doped in the polymer matrix. These guest-host-type polyme r films, which have no absorption in the blue-wavelength region, have second harmonic generation(SHG) activities without the electric-field poling process. The nonlinear optical coefficient d(33) is estimated a s 1.10 pm/V at a 15 wt % of dye concentration. The nonlinearity is sta ble at room temperature and at 120 degrees C. The SHG device is fabric ated using the nonpoled polymer film, and Cerenkov-type phase-matched SHG is observed. (C) 1995 American Institute of Physics.