Fig. 1. Energy level model for Er³⁺

Fig. 2. Experimental setup of gain measurement for Er∶LNOI waveguide

Fig. 3. Comparison of waveguide amplifier gain between simulation and experiment with 980 nm pump

Fig. 4. Comparison of waveguide amplifier gain between simulation and experiment with 1484 nm pump. (a) -50 dBm signal power; (b) 0 dBm signal power

Fig. 5. Comparison of waveguide amplifier gain between simulation and experiment at different waveguide lengths.(a) Internal net gain of waveguide amplifier with waveguide length of 2.8 cm under 1531.5 nm signal wavelength; (b) comparison of internal net gains between waveguide amplifiers with waveguide lengths of 2.58 cm and 1.62 cm under 1484 nm pump wavelength