Title :
Grating-coupled surface-emitting laser with a hyperbolic unstable resonator producing a stable focused output beam
Author :
Eriksson, N. ; Modh, P. ; Larsson, A.
Author_Institution :
Dept. of Microelectron., Chalmers Univ. of Technol., Goteborg, Sweden
Abstract :
A grating-coupled surface-emitting semiconductor laser has been integrated with a focusing diffractive beamforming element. A hyperbolic unstable resonator is used to introduce mode discrimination and suppress filamentation in a broad geometry, resulting in a 200-μm-wide coherent output. The light is focused 500 μm above the laser surface to a spot size of 5×7 μm. A remarkable beam stability is observed with very small spot size variation and beam-steering up to three times the threshold current under continuous operation.
Keywords :
diffraction gratings; laser beams; laser cavity resonators; laser modes; laser stability; optical focusing; semiconductor lasers; surface emitting lasers; 200 mum; 5 mum; 7 mum; beam stability; continuous operation; filamentation suppression; focusing diffractive beamforming element; grating-coupled surface-emitting laser; grating-coupled surface-emitting semiconductor laser; hyperbolic unstable resonator; mode discrimination; stable focused output beam; threshold current; very small spot size variation; Gratings; Laser beams; Laser feedback; Laser modes; Laser stability; Optical resonators; Optical surface waves; Semiconductor lasers; Surface emitting lasers; Waveguide lasers;
Journal_Title :
Photonics Technology Letters, IEEE
