Rare-earth doped glass waveguides prepared by pulsed laser deposition

Abstract

Rare-earth (Er,Yb) doped glass films are prepared by pulsed laser deposition onto different substrates: Si, fused quartz and Si with a silicon oxide buffer layer. Films grown in the presence of an oxygen pressure higher than 6 × 10-2 mbar have a refractive index close and slightly higher than that of the bulk material thus proving that the density of the films is high. Films thicker than 1 μm are multimode waveguides with a refractive index of 1.562 ± 0.003 and show losses higher than 10 dB/cm which seem to be related to surface roughness due both to the substrate quality and the deposition process.