Highly temperature insensitive quantum cascade lasers

An InP based quantum cascade laser (QCL) heterostructure emitting around 5 mu m is grown with gas-source molecular beam epitaxy. The QCL core design takes a shallow-well approach to maximize the characteristic temperatures, T(0) and T(1), for operations above room temperature. A T(0) value of 383 K and a T(1) value of 645 K are obtained within a temperature range of 298-373 K. In room temperature continuous wave operation, this design gives a single facet output power of 3 W and a wall plug efficiency of 16% from a device with a cavity length of 5 mm and a ridge width of 8 mu m. (C) 2010 American Institute of Physics. [doi:10.1063/1.3529449]