Thulium-Doped Tellurium Oxide Laser for Optical Communication at 2-µm Window

We demonstrate compact thulium-doped tellurium oxide microring lasers integrated on a low-loss silicon nitride platform with the output powers of up to 4.1 mW. We observe lasing in the wavelength range of 1.84–1.88 μm under 1.6 μm resonant pumping at 1.3 μm waveguide- microring gap size.