Experimental investigation of the lattice and electronic temperatures in Ga_(0.47)In_(0.53)As/Al_(0.62)Ga_(0.38)As_(1-x)Sb_x quantum-cascade lasers

摘要

The authors extracted the thermal resistance (R_L-9.6 K/W) and the electrical power dependence of the electronic temperature (R_e=12.5 K/W) of Ga_(0.47)In_(0.53)As/Al_(0.62)Ga_(0.38)As_(1-x)Sb_x quantum-cascade lasers (QCLs) operating at 4.9 μm, in the lattice temperature range of 60-90 K. The low electron-lattice coupling constant α= 10.4 K cm~2/kA can be related to the beneficial effect of the high conduction band offset, peculiar to the GaInAs/AlGaAsSb material system, on the electron leakage. The authors found an active region cross-plane thermal conductivity value k_⊥ = 1.8 ± 0.1 W/(K m), which is approximately three times larger than that measured in QCLs with GalnAs/AlInAs heterostructures.