Tunable fiber attenuator for electrically wet-driven micromirrors

Abstract

Herein we report an electronically controlled tunable fiber-optic attenuator that leverages the microfluidic electro-wetting effect, which enables a fine-tuning of the solid-liquid interface wetting angle to control the micro-reflector, thus regulating the lens fiber coupling efficiency. Theoretical calculations indicated an optical attenuation regulation effect of 0–45.0 dB in the voltage range of 0–30.0 V. Experimental results align closely with theoretical calculations, demonstrating an attenuation range of 0.59–43.0 dB within a voltage variation range of 0–25.0 V, with control accuracy of 0.56 dB. Our study unveils the potential for designing fiber-optic attenuators with varying tuning accuracy by precisely adjusting the solid-liquid interface wetting angle.