Low-noise, high-power optical amplifier

Abstract

A multi-stage lasing semiconductor optical amplifier (SOA) device amplifies an optical signal. The multi-stage SOA includes at least two SOA stages coupled in series. Each SOA stage includes a semiconductor gain medium and a laser cavity including the semiconductor gain medium. The medium is pumped above a lasing threshold for the laser cavity, which clamps the gain of the medium. An optical signal propagating through the medium is amplified by the gain-clamped medium. The SOA stages are characterized by a design parameter which varies from stage to stage. In a preferred embodiment, the design parameter includes a noise figure and a saturable power, with both parameters increasing as the optical signal propagates from stage to stage. As a result, the multi-stage SOA can achieve better noise performance and higher power outputs compared to comparable SOAs of constant noise figure and saturable power.

Dependencies are inferred from the claim text.