Japanese Journal of Applied Physics
All-Optical Inverted Operational Amplifier Derived from the Negative Nonlinear Absorption Effect
Yoshinobu Maeda
Abstract
An all-optical inverted operational amplifier derived from the negative nonlinear absorption effect in an erbium-yttrium aluminum garnet crystal was realized using an erbium-doped fiber amplifier and a feedback ring resonator. The inverted output modulation degree depended on the fiber amplifier gain and increased abruptly at a gain of more than 25 dB. The maximum value of the output modulation degree was 91% when the input modulation degree was 52%. The inverted output power was amplified by approximately 28 times the input power of 25 µW. A NOR-type logic gate operation was demonstrated using two optical signals of 1.53 µm.