Fig. 1. (a) Light-current-voltage (L-I-V) results of a 4.5 mm cavity with a 195 μm emitting width double-junction laser diode chip. (b) 100× optical microscope photograph of the front facet, near-field (NF) pattern and intensity profile in the slow-axis direction.

Fig. 2. (a) Plot showing the intensity of the image profile on the NF CCD, where the calculated full collimated residual angle is 8.19 mrad. (b) Plot showing the intensity of the image profile on the FF CCD.

Fig. 3. NF and FF test setup diagram of a double-junction laser diode chip. Laser diode chip, double-junction laser diode chip; F1 (FAC), fast-axis collimator of 600 EFL; attenuator, uncoated wedge prism; F2 and F3, cylindrical lenses with 200 and 150 mm EFL, respectively, in the fast-axis direction.

Fig. 4. (a) Sketch of the spectral beam-combining external cavity setup consisting of a double-junction chip, an FAC lens, an MLDG and an OC. (b) Schematic diagram showing the NF and FF test setup of the chip after the grating external cavity. F1 (FAC), fast-axis collimator with 600 μm EFL; attenuator, uncoated wedge prism; MLDG, multi-layer dielectric grating; F2 and F3, cylindrical lenses with 200 and 150 mm EFL, respectively, in the fast-axis direction; OC, output coupler.

Fig. 5. (a) Plot showing the intensity of the image profile on the NF CCD, 369.6 . The calculated full collimated residual angle after the external cavity is 2.46 mrad. (b) Plot showing the intensity of the image profile on the FF CCD, 1054.8 .

Fig. 6. (a) Schematic diagram of the module, taking advantage of the large height of the housing body allowed for integrating cooling channels within its base plate without increasing the volume or mass. (b) Optical model as well as the simulated near field on the fiber input end and far-field ex-fiber.

Fig. 7. (a) Plot showing the non-stabilized spectrum of the module tested under pulsed current conditions (3 A, 30 , 1 ). (b) Plot showing the non-stabilized spectrum of the module tested under CW operation and water-cooled conditions (25°C, 3 flow rate).

Fig. 8. (a) Plot showing the spectrum of the module as a function of the pump current. The interval between the two spectral peaks is approximately constant 3.6 nm. (b) Plot showing L-I-V results of the module. The maximal CW output power is 562 W and PCE exceeds 55% at a current of 24 A and a 25°C water flow.