Atomic-Layer Engineered Erbium-Doped Waveguide Amplifier\nwith a 14.4 dB Net Gain

Erbium-doped\nwaveguide amplifiers have recently sparked significant\ninterest due to their importance in photonic integrated circuits and\non-chip light sources. Erbium-doped thin films deposited through the\natomic layer deposition technique hold great potential for achieving\nexcellent optical performance and integration with various material\nplatforms. Here, we demonstrate hybrid erbium-doped waveguide amplifiers\nusing atomic layer deposition and conduct a comprehensive characterization\nof their gains and output powers. A 9.31 cm amplifier reaches net\ngains of 14.4 ± 1.2 dB at 1531.6 nm and 13.7 ± 1.8 dB at\n1550 nm. These correspond to directly measured off-chip gains of 10.5\n± 0.3 dB and 9.5 ± 0.8 dB at 1531.6 and 1550 nm, respectively.\nA maximum on-chip output power of 8.0 ± 1.6 dBm is achieved at\n1550 nm. The amplifier exhibits a broadband net gain exceeding 9 dB\nacross the C-band, with a low noise figure of 4.5 dB for an input\npower of <−18.6 dBm. This work paves the way for the future\ndevelopment of high-performance on-chip amplifiers and light sources.