High-net-gain erbium-doped hybrid waveguide amplifiers on chalcogenide photonic platform

Chalcogenide glasses (ChGs) have been widely used in integrated photonics due to their excellent properties of low loss and high nonlinearity. However, the performance of the active waveguide amplifiers is merely adequate. Here, a hybrid waveguide amplifier in Ge25Sb10S65 planar waveguide by a highly erbium-doped Al2O3 layer is demonstrated. High-quality Er
³⁺
: Al
2
O
3
thin film with high concentration of 9×10
²⁰
cm
⁻³
is fabricated by atomic layer deposition technique. And the GeSbS waveguide is manufactured by thermal evaporation and plasma etching. Signal enhancement up to 11.93 ± 0.3 dB and internal net gain of approximately 1.28 dB/cm are obtained at 1533 nm in the 1.5-cm-long and 0.8-cm-long waveguides upon 1480 nm pumping, respectively. The hybrid configuration is proved to be an efficient strategy to implement ChG-based integrated waveguide amplifiers.