High Temperature Operation of 5.5μm Strain-Compensated Quantum Cascaded Lasers

We develop 5.5-μm In_xGa_1-xAs/In_yAl_1-yAs strain-compensated quantum cascade lasers with InP and InGaAs cladding layers by using solid-source molecular-beam epitaxy. Pulse operation has been achieved up to 323K (50°C) for uncoated 20-μm-wide and 2-mm-long devices. These devices display an output power of 36mW with a duty cycle of 1% at room temperature. In continuous wave operation a record peak optical power of 10mW per facet has been measured at 83K.