BriVi - Brilliant high power violet emitting laser diodes

In the joint project violet emitting diode lasers and diode laser systems with high power and high brilliance are developed. The laser devices can possibly substitute conventional light sources in a high number of applications such as spectroscopy, metrology and medical diagnosis in order to realize more efficient, robust and compact hardware

In cooperation with research institutes and companies in Poland and Germany (Institute of High Pressure Physics of the Polish Academy of Sciences - Unipress, TopGaN und eagleyard Photonics GmbH) the whole production chain, including epitaxy of the wafers, chip-processing, mounting/ housing and characterization is covered.

In order to achieve a small linewidth in this wavelength region galliumnitride-based laser are produced with distributed Bragg reflector (DBR) or distributed feedback (DFB) and external cavity diode lasers (ECDL), respectively.  By using the laser diodes as driver for tapered amplifiers a high brilliance is achieved by increasing the optical output power while maintaining a high beam quality.

Schematic of a laser diode chip with distributed feedback (DFB). The detail image shows the electron microscopic image of the cross-section of a DFB grating.

At the FBH the epitaxy of the laser structures and the processing of the DFB gratings are developed. The figure shows a schematic of such a laser diode chip with distributed feedback and an electron microscopic image of the cross-section of a DFB grating. In order to achieve lateral coupling of the laser mode with the grating structure, a few 100 nm wide trenches with sufficient aspect ratio need to be etched in the waveguide of the laser structure. The FBH focusses on the optimization of the epitaxy and chip technologies necessary to realize such devices.

The project is partly financed by the European Regional Development Fund (ERDF).

Funding period:  10/01/14 – 09/30/1