We describe an optical pumping injection cavity (OPIC) edge-emitting laser
which employs GaSb/AlAsSb distributed Bragg reflectors above and below the
type-II "W" active region to form an etalon for the pump beam. A pulsed W-O
PIC laser emitting at 3.1-3.4 mu m displays an incident threshold pump inte
nsity of only 8 kW/cm(2) at 300 K, and incident power conversion efficienci
es per facet of 9% at 77 K and 4% at 275 K. (C) 1999 American Institute of
Physics. [S0003-6951(99)00545-8].