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arXiv · 1708.01981

Orbital-dependent quasiparticle scattering interference in 3R-NbS2

T. Machida·Y. Kohsaka·R. Suzuki·M. Ochi·K. Iwaya·R. Arita·T. Hanaguri·Y. Iwasa
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Abstract

A valley degree of freedom (DOF) in transition metal dichalcogenides with broken inversion symmetry can be controlled through spin and orbital DOFs owing to their valley-contrasting characters. Another important aspect of the spin and orbital DOFs is that they affect quasiparticle scattering processes that govern the valley lifetime. Here we combine quasiparticle-interference (QPI) imaging experiments and theoretical simulations to study the roles of the spin and orbital DOFs in 3R-NbS2. We find that the QPI signal arising from an inter-valley scattering is noticeably weaker than that caused by an intra-valley scattering. We show that this behavior is predominantly associated with the orbital DOF, signifying the different spin and orbital structures of spin-split bands at each valley. These findings provide important insights into understanding the valley-related transport properties.

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T. Machida, Y. Kohsaka, R. Suzuki, M. Ochi, K. Iwaya, R. Arita, T. Hanaguri, Y. Iwasa. 2017-08-07. Orbital-dependent quasiparticle scattering interference in 3R-NbS2. https://doi.org/10.1103/physrevb.96.075206

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