Quantum cascade lasers are unipolar semiconductor lasers covering a wide range of the
infrared and terahertz spectrum. Lasing action is achieved by using optical intersubband …

The terahertz (THz) quantum cascade laser (QCL), first demonstrated in 2002, is among the
most promising radiation sources in the THz region owing to its high output power and broad …

We review the most recent technological and application advances of quantum cascade
lasers, underlining the present milestones and future directions from the Mid-infrared to the …

Several competing technologies continue to advance the field of terahertz science; of
particular importance has been the development of a terahertz semiconductor quantum …

Terahertz quantum cascade lasers (QCLs) emit radiation due to intersubband optical
transitions in semiconductor superlattices that could be engineered by design. Among a …

We develop simple density-matrix models to describe the role of coherence in resonant-
tunneling (RT) transport of quantum-cascade lasers (QCLs). Specifically, we investigate the …

We analyze theoretically several crucial performance aspects of terahertz quantum cascade
lasers, such as the impact of do** on the threshold current, the relative importance of the …

Detailed simulations for terahertz quantum cascade lasers based on two-well designs are
presented. We reproduce the maximal operation temperatures observed and attribute the …

A simplified density-matrix model describing the population and coherence terms of four
states in a resonant phonon scattering based terahertz quantum cascade laser is presented …

n-type Ge/SiGe terahertz quantum cascade lasers are investigated using non-equilibrium
Green's functions calculations. We compare the temperature dependence of the terahertz …