High peak power (2.2W) superlattice quantum cascade laser

The improved optical power performance of superlattice quantum cascade lasers with a novel injector design allow ing the tunnelling of electrons into high energy states of the excited miniband is reported. At 8.4 mum and temperatures less than or equal to 120K, peak powers > 2W per facet are measured, corresponding to a record power of 88mW/stage. A slope efficiency of 160mW/A over a current range six times larger than the laser threshold is observed.