%0 Journal Article
%A Messaoudi, Omar
%A Ibañez-Azpiroz, Julen
%A Bouzar, Hamid
%A Lounis, Samir
%T Nondegenerate valleys in the half-metallic ferromagnet Fe / WS 2
%J Physical review / B
%V 97
%N 3
%@ 2469-9950
%C Woodbury, NY
%I Inst.
%M FZJ-2018-00906
%P 035404
%D 2018
%X We present a first-principles investigation of the electronic properties of monolayer WS2 coated with an overlayer of Fe. Our ab initio calculations reveal that the system is a half-metallic ferromagnet with a gap of ∼1 eV for the majority spin channel. Furthermore, the combined effect of time-reversal symmetry breaking due to the magnetic Fe overlayer and the large spin-orbit coupling induced by W gives rise to nondegenerate K and K′ valleys. This has a tremendous impact on the excited-state properties induced by externally applied circularly polarized light. Our analysis demonstrates that the latter induces a singular hot-spot structure of the transition probability around the K and K′ valleys for right and left circular polarization, respectively. We trace back the emergence of this remarkable effect to the strong momentum dependent spin-noncollinearity of the valence band involved. As a main consequence, a strong valley-selective magnetic circular dichroism is obtained, making this system a prime candidate for spintronics and photonics applications.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000419098500006
%R 10.1103/PhysRevB.97.035404
%U https://juser.fz-juelich.de/record/842699