Waveguide fabrication and high-speed in-line intensity modulation in 4-N,N-4 '-dimethylamino-4 '-N '-methyl-stilbazolium tosylate

We report the formation of thin-film waveguides of organic crystals by prec ision optical polishing and the fabrication of an electro-optic intensity m odulation device based on a thin-him waveguide of N,N-4'-dimethylamino-4'-N '-methyl-stilbazolium tosylate (DAST(R)) as an overlay on a side-polished f iber (SPF). Successful fabrication of single-crystal DAST(R) waveguides wit h thicknesses in the 20-25 mu m range have been produced. The waveguides we re investigated via an evanescent coupling technique using side-polished fi bers rather than traditional end-firing methods. Surface quality is believe d to have been sufficient for low-loss propagation. Electrodes were added t o the SPF/DAST(R) overlay architecture and intensity modulation observed ou t to 18 GHz. The device frequency response is believed to extend beyond 100 GHz under optimum conditions. (C) 1999 American Institute of Physics. [S00 03-6951(99)02704-7].