An Analytical Model of SH-LED for Gas Sensor Instrumentation in Mid-infrared (2-5μm) Region

In this paper, we present an analytical model of a P-InAs0.36Sb0.20P0.44/ n-InAs/n-InAs single heterostructure light emitting diode (SH-LED) suitable for use as source in gas detection instrumentation system based on optical absorption gas spectroscopy in the mid-infrared spectral region at room temperature. The model takes into account all dominating radiative and non-radiative recombination processes, interfacial recombination and self-absorption in the active layer of the SH-LED structure. The effect of various radiative and nonradiative recombination mechanisms on the quantum efficiency and hence output power of the LED has been evaluated. The output power of the SH-LED has been computed as a function of bias current and compared/ contrasted with the reported experimental results. Keywords— Gas instrumentation, Light emitting diode, Mid-infrared, Single heterostructure.