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

Watt-class semiconductor optical amplifiers (SOAs) at 1550 nm 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 > 30 dBm (1.2 W) of continuous wave ex-fiber power at 1550 nm [1] with 16 dB 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 10 Gbps using the differential phase shift keying (DPSK) communications format. Watt-class collimated and fiber-coupled SOAs are available and being shipped to customers now.