Improved performance due to suppression of spontaneous emission in tensile-strain semiconductor lasers

It is shown that application of biaxial tension to the active region of a bulk or quantum well semiconductor laser can significantly enhance TM gain compared to TE gain and reduce the threshold current density, due to suppression of spontaneous emission polarised in the growth plane of the laser structure. The differential gain is enhanced compared to unstrained structures and a larger peak gain can be achieved than in comparable structures under biaxial compression.