Electron-hole pair generation in terahertz-driven heterojunctions

Nonlinear dynamics involving electron transport in low-dimensional semiconductors driven by an intense terahertz (THz) electromagnetic radiation has recently become a central focus of many studies. We have theoretically studied electron transport and electron-hole pair generation-recombination rate in THz-driven InAs/AlSb heterojunctions, by considering multiple photon process and conduction-valence interband impact ionization. We consider the electron-acoustic-phonon and electron-polar-optical-phonon scatterings, and elastic scattering both from the remote charged impurities and from the background impurities. We have determined the field and frequency dependent electron-hole pair generation-recombination rate. It is show that impact ionization process plays an important role on electron transport in the intense THz-driven heterojunctions.