Curved Waveguide Array Diode Lasers for High-Brightness Applications

High-brightness diode laser arrays integrated with a phase shifter designed for single-lobe far-field pattern

“…3(a) and the output power up to 465 mW∕facet is achieved, which is one of the best reported results for high-brightness devices integrated with the phase shifter [14][15][16]. The threshold current is 390 mA and the external differential efficiency is 22%.…”

“…Superior to other phase shifters fabricated by facet coating and plate mounting [14,15], the integrated phase shifter in our device is easy to achieve technically, and it also reduces the bend loss in the curved waveguide arrays [16]. Although the carrier-induced variations of refractive index are avoided in the passive phase-shift region, the thermal effect generated by the absorption loss strongly affects the device performance.…”

“…Phase-shift structures have been applied to phase-locked laser arrays to convert the two-lobe pattern into single-lobe one, such as an external phase-shift plate [14] or an integrated phase-shift facet coating [15]. One report by Elarde et al [16] developed a laser array which combined the coupling region with the phaseshift region to transform the out-of-phase mode into the in-phase mode. However, the coupling region and the phase-shift region were designed to be a broad area waveguide and curved waveguides, respectively, which enhanced the mode mismatch between them.…”

Comprehensive design and analysis of diode laser arrays with an integrated phase shifter

“…Design of phase-locked diode laser arrays with integrated phase-shifters was firstly proposed by Ackley et al [10] and devices were experimentally achieved with an external phase-shift plate [11][12][13], or an integrated phaseshift facet coating [14]. A three-region design with curved waveguides as an integrated phase-shifter was reported to achieve the on-axis, diffraction-limited beam pattern, but only a low power in pulse mode was obtained [15]. Compared with structures mentioned above, we have developed a device which provided more effective phase-shift function with a simpler design, and achieved better results on high-brightness emission [16].…”