High-Power Broad-Area Lasers
FBH develops tailor-made laser diodes (in single-emitter and bar configurations) for partners and customers in research and industry for the pumping of solid-state lasers and for direct applications in material processing and medical technology.
The aim of our research work is to understand and address the limitations to power, efficiency and beam quality of high-power broad-area diode lasers. Further research topics include increasing reliability and reducing spectral linewidth in the wavelength range between 630–1200 nm. In addition, we are investigating novel device concepts, such as technology for monolithic wavelength stabilization.
Single emitters
We achieve high output powers by electrically pumping large-area devices with emitting apertures of 30 – 1200 µm and resonator lengths up to 8 mm. Applications range from remote sensing, illumination, pumping of solid state, fiber and gas lasers to measurement and control, medical technology, sensor technology and material processing.
Chip technology
- semiconductor layers by means of MOVPE
- monolithic gratings via surface etch technology or two step-epitaxial techniques
- contact windows by
- projection lithography
- implantation and isolating layers
- deposition of metallization
- thinning
- scribing, breaking & cleaving
- facet coating & passivation with extremely long lifetimes
Assembly
- hard, gold-tin soldered packaging
- open heat sinks (C-Mount)
- conduction cooled package (CCP)
- expansion matched submounts
- integrated double-sided heat-sinking
- additional FAC lenses (fast axis collimator) & external gratings possible
Typical data
- NIR range:
- up to 30 W QCW output power from diode lasers with 100 µm stripe width
- up to 60 W QCW output power from diode lasers with 400 µm stripe width (1 ms pulse width)
- high power density with peak values of more than 56 MW·cm-2 driven by a short-pulse source
- high efficiency > 65% at 10 W output power from single emitters with 90 µm stripe width
- 10 W reliable output power from diode lasers with monolithic integrated gratings with 90 µm stripe width
- high-power laser with vertical far field < 16° (95% power content)
- 17 W near-diffraction-limited emission from a single semiconductor light source
- reliable output power >120 W (1 ms, 200 Hz) from an aperture of 1.2 mm
- up to 7 W output power from a 30 µm aperture, with a beam parameter product of < 2 mm·mrad
- red spectral range:
- up to 1 W output power at 635 nm
- high efficiency of 37 % at 635 nm
- 654 nm lasers with reliable 2.7 W output power (100 µs, 35 Hz)
- 670 nm lasers with reliable 1.2 W CW output power
Laser bars
Laser bars consist of several broad-area lasers arranged laterally into a single component. It is thus possible to achieve an output power of more than 1500 W from a single source. Laser bars are used to pump solid-state, fiber and alkali-gas lasers (e.g. space applications and high-energy-class solid-state laser systems). They are also used in direct material processing, e.g. as sources for spectral beam combined systems. Other applications include free-space communications, printing and medical technology.
Typical wavelengths
650, 670, 780, 808, 850, 880, 920, 940, 980 and 1060 nm
Chip technology
- semiconductor layers by means of MOVPE
- monolithic gratings via surface etch technology or two step-epitaxial techniques
- contact windows by
- projection lithography
- implantation & isolating layers
- deposition of metallization
- thinning
- scribing, breaking & cleaving
- facet coating and passivation for extremely long lifetimes
Assembly
- hard, gold-tin soldered packaging
- conduction cooled package (CCP)
- expansion-matched submounts
- additional FAC lenses (fast axis collimator) & external gratings possible
Typical data
- NIR range:
- laser bars with output power up to 1000 W CW, up to 1500 W QCW on passive heat sinks, up to 2000 W QCW when tested at 203 K
- laser bars with narrow vertical far field for low loss, smile-insensitive external spectral stabilization
- laser bars with high efficiencies of >70% in the wavelength range from 808 nm to 980 nm
- high-brightness grating-stabilized mini-bars tailored for spectral beam combination applications
- high duty cycle, long resonator QCW laser bars for future high-energy systems
- efficient high-power bars of single-mode emitters for dense wavelength multiplexing (DWM) applications
- red spectral range (650 nm): output power up to 10 W CW on passive heat sinks
