Robust high-power single-mode semiconductor optical amplifiers at 1550nm for free space optical communications

Watt-class semiconductor optical amplifiers (SOAs) at 1550nm are an attractive alternative to replace erbium-doped fiber amplifiers (EDFAs) in various applications including free space optical communications (FSO), with the potential to be more efficient, compact, and cost-effective while providing high-power diffraction-limited output. We present a single mode fiber-coupled packaged SOA delivering >30dBm (1.2W) of continuous wave ex-fiber power at 1550nm with 16dB of overall gain, enabled by recent advancements in diffraction-limited output from tapered semiconductor amplifiers. Preliminary data communications measurements are presented, with an open eye diagram achieved with >1W of output power at 10Gbps using the differential phase shift keying (DPSK) communications format. Watt-class collimated and fiber-coupled SOAs are available and being shipped to customers now.