TY  - JOUR
AU  - Messaoudi, Omar
AU  - Ibañez-Azpiroz, Julen
AU  - Bouzar, Hamid
AU  - Lounis, Samir
TI  - Nondegenerate valleys in the half-metallic ferromagnet Fe / WS 2
JO  - Physical review / B
VL  - 97
IS  - 3
SN  - 2469-9950
CY  - Woodbury, NY
PB  - Inst.
M1  - FZJ-2018-00906
SP  - 035404
PY  - 2018
AB  - 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.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000419098500006
DO  - DOI:10.1103/PhysRevB.97.035404
UR  - https://juser.fz-juelich.de/record/842699
ER  -