Distributed feedback channel waveguide lasers in erbium- and ytterbium-doped Al2O3 on silicon

The favourable optical properties of aluminium oxide (Al2O3) waveguides make it an excellent laser gain medium for monolithic laser devices. Recently, low-loss erbium-doped aluminium oxide (Al2O3:Er³⁺) channel waveguide amplifiers have demonstrated internal net gain over a wavelength range of 80 nm (1500–1580 nm), with a peak gain of 2.0 dB/cm at 1533 nm [1]. Consequently, the first integrated Al2O3:Er³⁺ laser was demonstrated in a ring resonator geometry soon thereafter [2]. Due to the wide gain bandwidth, the laser was shown to operate on several wavelengths in the range 1530–1557 nm.