Terahertz lasing at room temperature: A numerical study of a vertical-emitting quantum cascade laser based on a quantum dot superlattice

We investigate room-temperature lasing of terahertz quantum cascade lasers using quantum dot chains as active material suitable for wireless communication and imaging technologies. To make band structure calculations for such extended systems of coupled quantum dots possible, we developed a linear combination of quantum dot orbitals method, based on single quantum dot wave functions. Our results demonstrate strong vertical emission of coupled quantum dots, reduced phonon coupling, and in-plane scattering, enabling room-temperature lasing with significantly reduced threshold current densities.

Automated summary

Room-temperature lasing of terahertz quantum cascade lasers was achieved using quantum dot chains as active material, enabling wireless communication and imaging technologies. By developing a method for band structure calculations of coupled quantum dots, strong vertical emission, reduced phonon coupling, and in-plane scattering were demonstrated, leading to room-temperature lasing with reduced threshold current densities.