Fast-to-slow axis mode imaging for brightness enhancement of a broad-area laser diode array

Fast-to-slow axis mode imaging for brightness enhancement of a broad-area laser diode array.

Broad-area laser (BAL) diodes have found use in numerous applications requiring multi-watt powers, but remain limited by poor spatial beam quality. A novel laser cavity that enhances the brightness of a BAL array has been demonstrated. Wavelength beam combining (WBC) is used to spatially overlap output from the emitters. Improved beam quality is achieved by imaging the fast-axis mode onto the s...

Spectral properties of a broad-area diode laser with off-axis external-cavity feedback

980 nm high brightness external cavity broad area diode laser bar.

We demonstrate off-axis spectral beam combining applied to a 980 nm high power broad area diode laser bar. The experiments yielded 9 W of optical power at 30 A of operating current and the measured M2 values of the combined beam from 12 emitters were 1.9 and 6.4 for the fast and the slow axis, respectively. The slow axis beam quality was 5-6 times better than the value obtained from a single em...

Mode stabilization of a laterally structured broad area diode laser using an external volume Bragg grating.

An external volume Bragg grating (VBG) is used for transverse and longitudinal mode stabilization of a broad area diode laser (BAL) with an on-chip transverse Bragg resonance (TBR) grating. The internal TBR grating defines a transverse low-loss mode at a specific propagation angle inside the BAL. Selection of the TBR mode was realized via the angular geometry of an external resonator assembly c...

1450-nm high-brightness wavelength-beam combined diode laser array.

We have demonstrated wavelength beam combining of a 1450-nm diode laser array with a novel smile compensation method. We have achieved 20-W cw from a 25-element single bar with an M(2) of 1.9 (fast axis) x 10 (wavelength-beam-combined dimension).