Erbium-doped tellurium oxide distributed Bragg reflector lasers on silicon nitride chips

We demonstrate integrated distributed Bragg reflector lasers on a hybrid platform composed of silicon nitride waveguides coated with erbium-doped tellurium dioxide. The asymmetrical laser cavities are enclosed by gratings patterned on the 2.2-cm-long waveguide walls. Cavities with varying grating strengths are studied, yielding laser efficiencies up to 0.36%, a minimum lasing threshold of 13 mW, and emission wavelengths between 1530 and 1565 nm.