Narrow Stripe Broad Area Lasers With High Order Distributed Feedback Surface Gratings

Decker, J.; Crump, P.; Fricke, J.; Maaßdorf, A.; Erbert, G.; Tränkle, G.

doi:10.1109/lpt.2014.2307115

Cited by 33 publications

(25 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…12 presents spectral maps for the two devices shown in Fig. 11, measured by collecting all emitted light into an integrating sphere that is connected to a high resolution spectrometer using a fiber, as described in [20]. The DFB-NBA without resonant anti-guiding shows similar behavior to the devices in [20], with around 1...6 spectral lines observed.…”

Section: Studies Seeking Further Improved Brightnessmentioning

confidence: 94%

“…However, for P op > 4 W, BPP is identical with or without resonant anti-guiding. As noted in [20], the number of spectral lines in DFB-NBAs is a good measure of the number of lateral guided modes that are present. Therefore, Fig.…”

Section: Studies Seeking Further Improved Brightnessmentioning

confidence: 99%

“…Monolithic wavelength stabilization is then introduced using surface etched high-order gratings, as described in [20], and shown schematically in Fig. 6.…”

Section: Status Of Distributed-feedback Narrow-stripe Ba Lasers (Dfb-mentioning

confidence: 99%

“…6. The vertical layer structure, device fabrication and assembly processes used are described in [20], with the vertical layer structure carefully designed to enable the manufacture of surface-etched gratings. The final realized devices have a cavity length of L = 6 mm, front and rear facet reflectivities of 0.8% and 98% respectively and are mounted junction side down on CuW carriers.…”

Section: Status Of Distributed-feedback Narrow-stripe Ba Lasers (Dfb-mentioning

confidence: 99%

“…7 for the electro-optic and beam properties of reference NBA lasers without grating stabilization, compared to reference devices from the same wafer that were fabricated using a conventional device geometry of W = 90 µm and L = 4 mm. The reference devices operate with η E = 59% at P op = 7 W, and the NBA devices operate with η E = 53% at P op = 7 W (57% at 5W), a 10% fractional loss, due to the increased electrical resistance (smaller contact area) and enhanced losses at the stripe edges for W = 30 µm [19][20]. BPP is simultaneously reduced from ~ 4 mm×mrad to ~ 2 mm×mrad.…”

Section: Status Of Distributed-feedback Narrow-stripe Ba Lasers (Dfb-mentioning

confidence: 99%

See 4 more Smart Citations

Development of high-power diode lasers with beam parameter product below 2 mm×mrad within the BRIDLE project

Crump

Decker

Winterfeldt

et al. 2015

High-Power Diode Laser Technology and Applications XIII

View full text Add to dashboard Cite

High power broad-area diode lasers are the most efficient source of optical energy, but cannot directly address many applications due to their high lateral beam parameter product BPP = 0.25 × Θ L 95% × W 95% (Θ L 95% and W 95% are emission angle and aperture at 95% power content), with BPP > 3 mm×mrad for W 95%~9 0µm. We review here progress within the BRIDLE project, that is developing diode lasers with BPP < 2 mm×mrad for use in direct metal cutting systems, where the highest efficiencies and powers are required. Two device concepts are compared: narrow-stripe broad-area (NBA) and tapered lasers (TPL), both with monolithically integrated gratings. NBAs use W 95% ~ 30 µm to cut-off higher order lateral modes and reduce BPP. TPLs monolithically combine a single mode region at the rear facet with a tapered amplifier, restricting the device to one lateral mode for lowest BPP. TPLs fabricated using ELoD (Extremely Low Divergence) epitaxial designs are shown to operate with BPP below 2mm×mrad, but at cost of low efficiency (<35%, due to high threshold current). In contrast, NBAs operate with BPP < 2 mm×mrad, but maintain efficiency >50% to output of > 7 W, so are currently the preferred design. In studies to further reduce BPP, lateral resonant anti-guiding structures have also been assessed. Optimized anti-guiding designs are shown to reduce BPP by 1 mm×mrad in conventional 90 µm stripe BA-lasers, without power penalty. In contrast, no BPP improvement is observed in NBA lasers, even though their spectrum indicates they are restricted to single mode operation. Mode filtering alone is therefore not sufficient, and further measures will be needed for reduced BPP.

show abstract

Section: Studies Seeking Further Improved Brightnessmentioning

confidence: 94%

Section: Studies Seeking Further Improved Brightnessmentioning

confidence: 99%

“…Monolithic wavelength stabilization is then introduced using surface etched high-order gratings, as described in [20], and shown schematically in Fig. 6.…”

Section: Status Of Distributed-feedback Narrow-stripe Ba Lasers (Dfb-mentioning

confidence: 99%

Section: Status Of Distributed-feedback Narrow-stripe Ba Lasers (Dfb-mentioning

confidence: 99%

Section: Status Of Distributed-feedback Narrow-stripe Ba Lasers (Dfb-mentioning

confidence: 99%

See 3 more Smart Citations