Spin-valley physics in strained transition metal dichalcogenides monolayers*

Transition metal dichalcogenides (TMDCs) are ideal candidates to explore the manifestation of spin-valley physics under external stimuli. Here, we investigate the influence of strain on the spin, orbital angular momenta and g-factors of monolayer TMDCs within first principles[1]. Our calculations reveal the behavior of direct exciton g-factors under the isolated impact of strain: tensile (compressive) strain increases (decreases) the absolute value of g-factors. Strain variations of ~1% modify the bright (A and B) exciton g-factors by ~0.3 (0.2) for W (Mo) based compounds and the dark exciton g-factors by ~0.5 (0.3) for W (Mo) compounds, suggesting that strain can be responsible for g-factor fluctuations observed experimentally. We complete our analysis for the Γ and Q valleys, revealing that spin degree of freedom dominates. This fundamental microscopic insight into the role of strain in the spin-valley physics of TMDCs is crucial to understand recent experiments[2,3]. [1] Faria Junior et al., NJP 24, 083004 (2022). [2] Covre, Faria Junior et al., Nanoscale 14, 5758 (2022). [3] Blundo, Faria Junior et al., PRL 129, 067402 (2022).