420 W pulse power from a 905 nm distributed bragg reflector laser with multiple active regions and tunnel junctions

Abstract We report a record-high pulse power of 420 W or a pulse energy of 4.2 μJ at a pulse current of 210 A, emitted by a single distributed Bragg reflector broad-area laser with 5 active regions separated by 4 tunnel junctions. The laser is operated with nanosecond current pulses at a repetition frequency of 10 kHz so that optical pulses with a width of 10 ns are emitted. The emission spectrum exhibits a spectral peak at approximately 905 nm at 25 °C with a spectral width of less than 0.2 nm and a temperature-related shift of 63 pm K −1 . We also investigate the dependence of the output power on cavity length and number of active regions. A 4 mm long laser with 3 active regions achieves a pulse power of 272 W at 150 A. At the same current, 2 mm long lasers with 3 and 5 active regions achieve output powers of 167 W and 283 W, respectively. Despite its shorter cavity, the 2 mm long 5 active region laser delivers 10 W more output power at 150 A than the 4 mm long laser with 3 active regions. All lasers under study have a p-contact stripe width of 200 μm.