O'Callaghan, JR,Houlihan, J,Voignier, V,Huyet, G,McInerney, JG,Corbett, B,O'Brien, PA;

2002

January

IEEE Photonics Technology Letters

Focusing properties of high brightness gain tailored broad-area semiconductor lasers

Validated

()

gain control semiconductor lasers laser beam focusing laser thermal factors

14

9

11

In this letter, we present a simple broad-area semiconductor laser using a current spreading layer to modify the transverse gain profile. The device exhibits excellent spatial coherence to total output powers of 2.5 W under pulsed operation. Devices have been focused down to a spot size of approximately 5 mum full-width at half-maximum at 2.5 W, with the beam profile and position remaining stable over the entire range of operation. Under continuous-wave operation, thermal effects reduce spatial coherence leading to a significantly increased spot size and loss of beam stability. This work demonstrates the advantages of modifying the transverse gain profile, and how it can be used to produce high brightness devices required for single-mode fiber coupling.