Recent Progress in GaN Based Laser Development

Questions? Contact Peggy Morgan at 647-1778 or by email at [email protected]
Besides the improvement of GaN/GaInN laser technology leading to lower threshold current densities, the most interesting recent development is that of distributed feedback (DFB) lasers with first and second order gratings. These lasers exhibit single mode emission which can be precisely tuned through the periodicity of the grating (typically 60 nm for first order). DFB and DBR gratings are produced by etching in the case of index coupling. A new type of single mode laser is the laterally complex coupled DFB laser where a ridge waveguide is coupled to an absorbing array of lateral metal stripes. Important for electrically pumped lasers is the quality of the starting material grown on saphire or SiC substrates. Excellent results have been obtained by employing AIN nucleation layers with slight oxygen doping.
Stuttgart University, Germany
Details to follow.