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arXiv · 1512.01590

Kondo screening in two-dimensional $p$-type transition-metal dichalcogenides

Michael Phillips·Vivek Aji
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Abstract

Systems with strong spin orbit coupling support a number of new phases of matter and novel phenomena. This work focuses on the interplay of spin orbit coupling and interactions in yielding correlated phenomena in two dimensional transition metal dichalcogenides. In particular we explore the physics of Kondo screening resulting from the lack of centro-symmetry, large spin splitting and spin valley locking in hole doped systems. The key ingredients are i) valley dependent spin-momentum locking perpendicular to the two dimensional crystal; ii) single nondegenerate Fermi surface per valley, and iii) nontrivial Berry curvature associated with the low energy bands. The resulting Kondo resonance has a finite triplet component and nontrivial momentum space structure which facilitates new approaches to both probe and manipulate the correlated state. Using a variational wave function and the numerical renormalization group approaches we study the nature of the Kondo resonance both in the absence and presence of circularly polarized light. The latter induces an imbalance in the population of the two valleys leading to novel magnetic phenomena in the correlated state.

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Michael Phillips, Vivek Aji. 2017-06-02. Kondo screening in two-dimensional $p$-type transition-metal dichalcogenides. https://doi.org/10.1103/physrevb.95.075103

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