We report on the experimental study of the electronic and thermal properties in state of art Sb-based quantum-cascade lasers (QCLs) operating in the range 4.3-4.9 mu m. This information has been obtained by investigating the band-to-band photoluminescence signals, detected by means of an InGaAs-array detector. This technique allowed to probe the spatial distribution of conduction electrons as a function of the applied voltage and to correlate the quantum design of devices with their thermal performance. We demonstrate that electron transport in these structures may be insufficient, thus affecting the tunneling of electrons and the electronic recycling and cascading scheme. Finally, we present the first measurement of the electronic and lattice temperatures and of the electron-lattice coupling in Sb-based QCLs based on a quaternary-alloy. We 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)ln(0.53)As/Al0.62Ga0.38As1-xSbx structures operating at 4.9 mu m, in the lattice temperature range 60 K - 90 K. The corresponding electron-lattice coupling (alpha= 9.5 Kcm(2)/kA) reflects the efficient electronic cooling via optical phonon emission. The experimental normalized thermal resistance R-L(*) = 3.9 Kxcm/W demonstrates the beneficial use of quaternary thicker barriers in terms of device thermal management.
|Titolo:||Electronic and Thermal Properties of Sb-based QCLs operating in the first atmospheric window|
|Data di pubblicazione:||2007|
|Nome del convegno:||Conference on Novel in - Plane Semiconductor Lasers VI|
|Digital Object Identifier (DOI):||10.1117/12.698576|
|Appare nelle tipologie:||4.1 Contributo in Atti di convegno|