InGaN tapered laser diodes

InGaN laser diodes were fabricated with a tapered resonator in order to combine high quality of the lasing mode, characteristic for narrow stripe lasers, with high optical power, expected from wide area devices and to reduce current density responsible for device degradation. A number of devices were tested with taper angles between 2° and 5° and various taper lengths. It is demonstrated that, with the proper choice of device geometry, it is possible to obtain an almost singlemode operation characterised by an M² parameter as low as 2.1 at optical power of 200 mW.