Spin-valley locking in the normal state of a transition-metal dichalocogenide superconductor

Abstract

The metallic transition-metal dichalcogenides (TMDCs) are benchmark systems for studying and controlling intertwined electronic orders in solids, with superconductivity developing upon cooling from a charge density wave state. The interplay between such phases is thought to play a critical role in the unconventional superconductivity of cuprates, Fe-based, and heavy-fermion systems, yet even for the more moderately-correlated TMDCs, their nature and origins have proved highly controversial. Here, we study a prototypical example, $2H$-NbSe${}_2$, by spin- and angle-resolved photoemission and first-principles theory. We find that the normal state, from which its hallmark collective phases emerge, is characterised by quasiparticles whose spin is locked to their valley pseudospin. This results from a combination of strong spin-orbit interactions and local inversion symmetry breaking. Non-negligible interlayer coupling further drives a rich three-dimensional momentum-dependence of the underlying Fermi surface spin texture. Together, these findings necessitate a fundamental re-investigation of the nature of charge order and superconducting pairing in NbSe${}_2$ and related TMDCs.

7 pages, 4 figures

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• Fermi Surface Nesting and the Origin of the Charge Density Wave in NbSe${}_2$
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• Primary role of the barely occupied states in the charge density wave formation of NbSe2
• k-resolved susceptibility function of 2H-TaSe2 from angle-resolved photoemission
• A spin- and angle-resolving photoelectron spectrometer

Cited by in corpus (53)

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• Pure Spin Photocurrent in Non-centrosymmetric Crystals: Bulk Spin Photovoltaic Effect
• Theory of Laser-Controlled Competing Superconducting and Charge Orders
• Graphene-WS${}_2$ heterostructures for tunable spin injection and spin transport
• Robust parity-mixed superconductivity in disordered monolayer transition metal dichalcogenides
• Magnetic Proximity-Induced Superconducting Diode Effect and Infinite Magnetoresistance in van der Waals Heterostructure
• Yu-Shiba-Rusinov states in the charge-density modulated superconductor NbSe2
• Excitonic structure of the optical conductivity in MoS${}_2$ monolayers
• Spin-valley locking, bulk quantum Hall effect and chiral surface state in a noncentrosymmetric Dirac semimetal BaMnSb${}_2$
• Narrow-band anisotropic electronic structure of ReS${}_2$
• Ising superconductors: Interplay of magnetic field, triplet channels, and disorder
• Morphology Control of Epitaxial Monolayer Transition Metal Dichalcogenides
• Misfit layer compounds: a platform for heavily-doped two-dimensional transition metal dichalcogenides
• Every-other-layer Dipolar Excitons in a Spin-Valley locked Superlattice
• Magnetoanisotropic spin-triplet Andreev reflection in ferromagnet-Ising superconductor junctions
• Yu-Shiba-Rusinov states of impurities in a triangular lattice of NbSe${}_2$ with spin orbit coupling
• Topological superconductivity from magnetic impurities on monolayer NbSe${}_2$
• Band splitting with vanishing spin polarizations in noncentrosymmetric crystals
• Strain-induced stripe phase in charge ordered single layer NbSe${}_2$
• Fermiology and electron-phonon coupling in the 2H and 3R polytypes of NbS${}_2$
• Hidden Physical Effects in Non-centrosymmetric Crystals
• Protection of Ising spin-orbit coupling in bulk misfit superconductors
• Unidirectional Kondo scattering in layered NbS2
• Engineering nodal topological phases in Ising superconductors by magnetic superstructures
• Revealing the two-dimensional electronic structure and anisotropic superconductivity in a natural van der Waals superlattice (PbSe)${}_{1.14}$NbSe${}_2$
• Hidden spin-orbital texture at the $\bar{\Gamma }$-located valence band maximum of a transition metal dichalcogenide semiconductor
• Control of Competing Superconductivity and Charge Order by Non-equilibrium Currents
• Optical induced Spin Current in Monolayer NbSe${}_2$
• Topological Ising pairing states in monolayer and trilayer TaS${}_2$
• Enhanced exciton-exciton collisions in an ultra-flat monolayer MoSe2 prepared through deterministic flattening
• In situ controllable magnetic phases in doped twisted bilayer transition-metal dichalcogenides
• Charge to Spin Conversion in van der Waals Metal NbSe2
• Symmetry manipulation of nonlinear optical effect for metallic TMDC
• Charge Density Waves and the Effects of Uniaxial Strain on the Electronic Structure of 2H-NbSe${}_2$
• Double refraction and spin splitter in a normal-hexagonal semiconductor junction
• Interplay of crystal thickness and in-plane anisotropy and evolution of quasi-one dimensional electronic character in ReSe${}_2$
• Moiré Superstructures in Marginally-Twisted NbSe${}_2$ Bilayers
• Nonlinear optical Hall effect of few-layered NbSe2
• Unconventional pairing in Ising superconductors: Application to monolayer NbSe${}_2$
• Doping Dependence of Spin-Momentum Locking in Bismuth-Based High-Temperature Cuprate Superconductors
• Hybrid-Order Topological Phase And Transition in 1H Transition Metal Compounds
• Spin-Valley Locking in 2H-TaS2 and Its Co-Intercalated Counterpart: Roles of Surface Domains and Co Intercalation
• Substrate pre-sputtering for layer-by-layer van der Waals epitaxy of 2D materials
• Examining Experimental Raman Mode Behavior in Mono- and Bi-layer 2H-TaSe${}_2$ via Density Functional Theory
• Phonon dynamics of a bulk WSe${}_2$ crystal excited by ultrashort near-infrared pulses
• Resonant interlayer coupling in NbSe${}_2$-graphite epitaxial moir{é} superlattices
• Evidence of Spin-Valley Coupling in Dirac Material BaMnBi2 Probed by Quantum Hall Effect and Nonlinear Hall Effect
• Plasmon Engineering in Intercalated 2H-TaS${}_2$
• Yu-Shiba-Rusinov States in Ising Superconductors
• Probing Quantum Geometric Phases via Scanning Tunneling Microscopy
• Magnetic Frustration Enforced Electronic Reconstruction in Ni intercalated NbSe${}_2$: Suppression of Electronic Orders