Power coupling of two broad area laser diodes with external feedback

The power from two similar diode laser systems with a center wavelength of 810 nm was added via polarization coupling. Each system consisted of a 1 μm x 200 μm broad area laser diode applied with external feedback. A power of 1.2 W, corresponding to 40% of the freely running system, with an M 2 value of 1.5 were obtained in the coupled output beam when operating the diodes at a current of three times the threshold current.