Fill Factor Bars Research Articles

Thin-film filter, wavelength-locked, multi-laser cavity for dense wavelength beam combining of broad-area laser diode bars.

We report on individual wavelength locking of a multiplet of 100-μm broad-area laser diode emitters arranged on a 50% fill-factor bar by means of a single external multi-laser cavity using an ultra-narrowband thin-film filter as a dispersive optical element. The achieved wavelength-locked output power is 216 W, corresponding to an electrical-to-optical conversion efficiency of about 49.7%. The 45 emitters of the laser diode bar are stabilized within a spectral range of about 6.4 nm. Our approach is suited for killowatt-class dense wavelength beam combining of direct diode lasers.

>700 W continuous-wave output power from single laser diode bar

>700 W continuous-wave output power has been demonstrated from a single 1 cm-wide laser bar (∼940 nm) with 77% fill factor. Maximum power conversion efficiency (PCE) of 65% has been achieved. Facet power density of 170 mW/µm and maximum PCE of 69% have been measured for 10% fill-factor bars with 3 mm cavity length.

Focus on Lasers and Optics

Focus on Lasers and Optics

High performance laser diode bars with aluminum-free active regions

We present operating and lifetest data on 795 and 808 nm bars with aluminum-free active regions. Conductively cooled bars operate reliably at CW power outputs of 40 W, and have high efficiency, low beam divergence, and narrow spectra. Record CW powers of 115 W CW are demonstrated at 795 nm for 30% fill-factor bars mounted on microchannel coolers. We also review QCW performance and lifetime for higher fill-factor bars processed on identical epitaxial material.