Advancements in high brightness tapered diode laser amplifiers

High brightness semiconductor diode lasers can provide tremendous system-level advantages for many applications. Recent advancements in InP-based edge-emitting diode lasers operating in the 1500 – 1600 nm wavelength band could enable compact, direct diode solutions with performance metrics that previously could only be met by fiber-based lasers or solid-state laser systems. We report on high power, high beam quality diode lasers at 1550 nm based on a tapered chip architecture. We have demonstrated ⪆5 W of continuous wave output power at room temperature, with a slow axis beam propagation factor M2 of 1.1, corresponding to a slow axis linear brightness of 9.2 W mm^-1 mrad^-1. We have also demonstrated a fully packaged watt-class single mode fiber-coupled Semiconductor Optical Amplifier (SOA) based on this technology. This package delivers ⪆30 dBm (1.2 W) ex-fiber saturation output power, ten times higher saturation power than the prior state-of-the-art. This result is achieved with an input seed power of 30 mW (approximately 15 dBm), corresponding to an overall gain of approximately 16 dB. To demonstrate the functionality of the SOA, we have carried out linewidth measurements and data transmission measurements. These tapered lasers and amplifiers offer great potential benefit for many pumping and direct use applications.