Amorphous As2S3 Doped with Transition Metals: An Ab Initio Study of Electronic Structure and Magnetic Properties

Crystalline transition-metal chalcogenides are the focus of solid state research. At the same time, very little is known about amorphous chalcogenides doped with transition metals. To close this gap, we have studied, using first principle simulations, the effect of doping the typical chalcogenide glass As2S3 with transition metals (Mo, W and V). While the undoped glass is a semiconductor with a density functional theory gap of about 1 eV, doping results in the formation of a finite density of states (semiconductor-to-metal transformation) at the Fermi level accompanied by an appearance of magnetic properties, the magnetic character depending on the nature of the dopant. Whilst the magnetic response is mainly associated with d-orbitals of the transition metal dopants, partial densities of spin-up and spin-down states associated with arsenic and sulphur also become slightly asymmetric. Our results demonstrate that chalcogenide glasses doped with transition metals may become a technologically important material.

Automated summary

Crystalline transition-metal chalcogenides are extensively studied, while there is limited understanding of amorphous chalcogenides doped with transition metals. To fill this knowledge gap, we conducted first principle simulations to investigate the effect of transition metal doping on the typical chalcogenide glass As2S3. Our results show that doping leads to a transformation from a semiconductor to a metal, with the appearance of magnetic properties. This opens up the possibility of chalcogenide glasses doped with transition metals becoming a technologically important material.