Silver and potassium ion-exchanged waveguides in glasses doped with PbS semiconductor quantum dots

We present a detailed analysis of potassium-sodium and silver-sodium ion-exchange processes for fabricating waveguides in glass doped with PbS semiconductor quantum dots. We compare the propagation losses of these waveguides, and we discuss the sources of these losses. In addition, we demonstrate a fourfold reduction in the propagation loss previously reported for potassium-sodium ion-exchanged waveguides and show that waveguides can be produced at additional quantum-dot resonances using both methods. We show that the near-infrared optical properties of these quantum dots remain intact by comparing the waveguide and bulk (unguided) luminescence spectra. Measurements of the near-field mode profiles show a high level of field confinement, which make these waveguides ideal for nonlinear optical (high-intensity) applications.