Ion-exchanged tapered waveguide laser in neodymium-doped BK7 glass

Description/Abstract

We report the first operation of a planar dielectric tapered waveguide laser. The waveguide lasers are fabricated by potassium ion-exchange in Nd3+-doped BK7 glass, and consist of a single-mode channel waveguide of a few microns width followed by a linear taper up to a broad region with a width of ~180μm. A slope efficiency of 42% is found in both the tapers and standard channel waveguides fabricated on the same substrate, indicating similar internal losses and hence the low-loss nature of the tapered beam expansion. The output from either end of the tapered structure is found to be near to diffraction-limited.