Fig. 7: Experimental setup for continuous-wave (CW) characterization of the device.

A tunable laser (Santec TSL-710) tuned to the pump resonance is amplified by an Erbium-doped fiber amplifier (Keopsys, EDFA). An isolator and a variable optical attenuator (VOA) regulate the input power, while a fiber optical filter suppresses amplified spontaneous emission (ASE). The signal is then coupled to the chip using UHNA-7 fiber spliced to match the integrated inverse taper coupler, with index matching gel ensuring stable optical contact.