Scattering-rate approach for efficient prediction of temperature-dependent characteristics of mid-infrared quantum cascade lasers

Abstract

A computationally efficient temperature-dependent model for scattering processes in mid-infrared quantum cascade lasers is developed. In this approach, the total intersubband scattering rate is described as the product of the overlap integral for the squared moduli of the envelope functions and a form factor that depends on transition energy, temperature, and material. Both inelastic and elastic scattering processes are included in the treatment. The model is used to calculate the temperature-dependent threshold current density $ {J_{{\rm th}}}(T) $Jth(T) in a 10-period strain-compensated InGaAs–InAlAs mid-infrared quantum cascade laser structure and determine the characteristic temperature $ {T_0} $T0 in $ {J_{{\rm th}}}(T) = {J_0}\exp {(T/{T_0})} $Jth(T)=J0exp⁡(T/T0). The effect of doping is also modeled.