Orbital gyrotropic magneto-electric effect and its strain engineering in monolayer Nb$X_2$

Abstract

Electrical control of the orbital degrees of freedom is an important area of research in the emerging field of "orbitronics." Orbital {\it gyrotropic} magneto-electric effect (OGME) is the generation of an orbital magnetization in a nonmagnetic metal by an applied electric field. Here, we show that strain induces a large GME in the monolayer Nb$X_2$ ($X=$ S, Se) normal to the plane, primarily driven by the orbital moments of the Bloch bands as opposed to the conventional spin magnetization, without any need for spin-orbit coupling. The key physics is captured within an effective two-band valley-orbital model and it is shown to be driven by three key ingredients: the intrinsic valley orbital moment, broken $C_{3z}$ symmetry, and strain-induced Fermi surface changes. The effect can be furthermore switched by changing the strain condition, with potential for future device applications.

References in corpus (25)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Coupled spin and valley physics in monolayers of MoS2 and other group-VI dichalcogenides
• Maximally-localized generalized Wannier functions for composite energy bands
• Maximally-localized Wannier functions for entangled energy bands
• Evidence of Ising pairing in superconducting NbSe${}_2$ atomic layers
• Three-band tight-binding model for monolayers of group-VIB transition metal dichalcogenides
• Experimental demonstration of continuous electronic structure tuning via strain in atomically thin MoS2
• Berry phase correction to electron density of states in solids
• Ultrafast collinear scattering and carrier multiplication in graphene
• Muffin Tin Orbitals of Arbitrary Order
• Electrical control of the valley Hall effect in bilayer MoS2 transistors
• Monolayer MoS2: trigonal warping, "Γ-valley", and spin-orbit coupling effects
• Current induced electron spin polarization in strained semiconductors
• Magnetoelectric effects and valley controlled spin quantum gates in transition metal dichalcogenide bilayers
• Gyrotropic magnetic effect and the magnetic moment on the Fermi surface
• Theory of strain in single-layer transition metal dichalcogenides
• Gyrotropic effects in trigonal tellurium studied from first principles
• Current-induced Orbital and Spin Magnetizations in Crystals with Helical Structure
• Giant Orbital Magneto-electric effect and Current-driven Magnetization Switching in Twisted Bilayer Graphene
• Intrinsic orbital moment and prediction of a large orbital Hall effect in the 2D transition metal dichalcogenides
• Intrinsic orbital and spin Hall effects in monolayer transition metal dichalcogenides
• Manipulating Spin-polarized Photocurrent in 2D Transition Metal Dichalcogenides
• Valley-dependent spin transport in monolayer transition-metal dichalcogenides
• A Tight Binding Approach to Strain and Curvature in Monolayer Transition-Metal Dichalcogenides
• Pancharatnam-Berry phase and kinetic magnetoelectric effect in a three-dimensional helical crystal (Te)

Cited by in corpus (8)

• Orbital Hall effect as an alternative to valley Hall effect in gapped graphene
• Orbital angular momentum of Bloch electrons: equilibrium formulation, magneto-electric phenomena, and the orbital Hall effect
• Orbital magnetoelectric effect in zigzag nanoribbons of p-band systems
• Orbital magnetoelectric effect in nanoribbons of transition metal dichalcogenides
• Orbitronics in Two-dimensional Materials
• Quantum theory of the Intrinsic Orbital Magnetoelectric Effect in itinerant electron systems at finite temperatures
• Electrically tunable and reversible magnetoelectric coupling in strained bilayer graphene
• Orbital Gravito-Magnetoelectric response and Orbital magnetic quadrupole moment correction