Thulium-doped tellurium oxide waveguide amplifier with 7.6 dB net gain on a silicon nitride chip.

Abstract

We report on thulium-doped waveguide amplifiers integrated on a low-loss silicon nitride platform. The amplifier structure consists of a thulium-doped tellurium oxide thin film coated on a silicon nitride strip waveguide on silicon. We determine a waveguide background loss of 0.7dB/cm at 1479nm based on the quality factor measured in microring resonators. Gain measurements were carried out in straight and 6.7-cm-long s-bend waveguides realized on a 2.2-cm-long chip. We measure internal net gain over the wavelength range 1860-2000nm under 1620nm pumping and up to 7.6dB total gain at 1870nm, corresponding to 1.1dB/cm. These results are promising for the realization of highly compact thulium-doped amplifiers in the emerging 2μm band for silicon-based photonic microsystems.