WAVE-GUIDES IN LTB (LI2B4O7) BY HE+ IMPLANTATION

Planar optical waveguides are formed in Y-cut LTB materials by He+ ion implantation. The profiles of the ordinary and the extraordinary refr active indices are determined from m-line spectroscopy and by using an IWKB method. The positions of the optical barriers are in good agreem ent with the calculated average penetration depth of the ions. The bes t coupling efficiency and light confinement are obtained with TM (n(o) ) modes, but this could be due to the used crystal cut (Y-cut) with re spect to the propagation direction.