Fig. 1. Measured vertical far-field characteristic of the laser chip.

Fig. 2. Schematic cross-sectional view of the semiconductor structure.

Fig. 3. high-power QCW laser for kW-pump modules. The chip is mounted on a plated AlN substrate. The size of the submount is .

Fig. 4. Simulated temperature distribution at the front facet after 1 ms pulse operation and at a dissipation power of 24 W. The laser reaches a maximum temperature rise of 10.9 K in the central emitter.

Fig. 5. Calculated variation of junction temperature with time (transient analysis) for the laser chip mounted on an AlN submount.

Fig. 6. LI characteristic ( ms,  Hz, ) of the SQW and DQW structures (, ).

Fig. 7. Output power of the DQW array at 40 A as a function of the front-facet reflectivity.

Fig. 8. LIV curve of the DQW structure with pitch.

Fig. 9. (a) Measured LI characteristic dependent on the emitter pitch (number of emitters) and (b) corresponding plot of the optical/dissipation power per stripe against the number of emitters at 35 W overall optical power.

Fig. 10. Spectral characteristic of the device for different optical power levels. The spectrum is broadened due to a thermal chirp.

Fig. 11. Lateral (a) near- and (b) far-field profiles of the DQW and SQW laser at 35 W output power ( ms,  Hz, ).

Fig. 12. Dependence of the lateral far-field of the DQW structure on the emitter pitch at  W ( ms,  Hz, ).

Fig. 13. COD test. Chip structure: DQW, , .

Fig. 14. Aging test of 25 DQW lasers after burn-in ( A,  ms,  Hz). Measurement:  A,  ms,  Hz.

Fig. 15. Aging test of 18 SQW lasers after burn-in ( A,  ms,  Hz). Measurement:  A,  ms,  Hz.