Observation of gigantic spin conversion anisotropy in bismuth

Abstract

Whilst the g-factor can be anisotropic due to the spin-orbit interaction (SOI), its existence in solids cannot be simply asserted from a band structure, which hinders progress on studies from such the viewpoints. The g-factor in bismuth (Bi) is largely anisotropic; especially for holes at T-point, the g-factor perpendicular to the trigonal axis is negligibly small (< 0.112), whereas the g-factor along the trigonal axis is very large (62.7). We clarified in this work that the large g- factor anisotropy gives rise to the gigantic spin conversion anisotropy in Bi from experimental and theoretical approaches. Spin-torque ferromagnetic resonance was applied to estimate the spin conversion efficiency in rhombohedral (110) Bi to be 17%, which is unlike the negligibly small efficiency in Bi(111). Harmonic Hall measurements supports the large spin conversion efficiency in Bi(110). This is the first observation of gigantic spin conversion anisotropy as the clear manifestation of the g-factor anisotropy. Beyond the emblematic case of Bi, our study unveiled the significance of the g-factor anisotropy in condensed-matter physics and can pave a pathway toward establishing novel spin physics under g-factor control.

arXiv comment28 pages, 7 figures

References in corpus (30)

• Topological Insulators
• Topological insulators and superconductors
• Weyl and Dirac Semimetals in Three Dimensional Solids
• Spin torque switching with the giant spin Hall effect of tantalum
• Dissipationless Quantum Spin Current at Room Temperature
• Spin Torque Ferromagnetic Resonance Induced by the Spin Hall Effect
• Direct electronic measurement of the spin Hall effect
• Spin transfer torque devices utilizing the giant spin Hall effect of tungsten
• Symmetry and magnitude of spin-orbit torques in ferromagnetic heterostructures
• Layer thickness dependence of the current induced effective field vector in Ta|CoFeB|MgO
• Quantitative characterization of the spin orbit torque using harmonic Hall voltage measurements
• Scaling of spin Hall angle in 3d, 4d and 5d metals from Y3Fe5O12/metal spin pumping
• Dependence of the Efficiency of Spin Hall Torque on the Transparency of Pt-Ferromagnetic Layer Interfaces
• Interplay of spin-orbit torque and thermoelectric effects in ferromagnet/normal metal bilayers
• Anomalous Spin-Orbit Torques in Magnetic Single-Layer Films
• Transport Properties and Diamagnetism of Dirac Electrons in Bismuth
• Self-induced inverse spin Hall effect in permalloy at room temperature
• Bi(111) thin film with insulating interior but metallic surfaces
• The spin Hall effect of Bi-Sb alloys driven by thermally excited Dirac-like electrons
• Relation between spin Hall effect and anomalous Hall effect in 3$d$ ferromagnetic metals
• Angle-resolved Landau spectrum of electrons and holes in bismuth
• Giant spin Hall angle in the Heusler alloy Weyl ferromagnet Co${}_2$MnGa
• Transport and spin conversion of multi-carriers in semimetal bismuth
• Magnetoresistance and valley degree of freedom in bulk bismuth
• Origin of the large anisotropic g-factor of holes in bismuth
• Spin projection and spin current density within relativistic electronic transport calculations
• Self-current induced spin-orbit torque in FeMn/Pt multilayers
• Anomalous sign inversion of spin-orbit torque in ferromagnetic/nonmagnetic bilayer systems due to self-induced spin-orbit torque
• Intrinsic and Extrinsic Spin Hall Effects of Dirac Electrons
• Self-induced spin-orbit torques in metallic ferromagnets

Cited by in corpus (5)

• Intrinsic orbital and spin Hall effect in bismuth semimetal
• Charge to spin conversion in atomically thin bismuth
• Temperature dependence of charge-to-spin conversion in rhombohedral (110) bismuth thin film
• Charge-to-spin conversion in epitaxial and polycrystalline Bi and Bi/Ag layers
• Investigating spin and orbital effects via spin-torque ferromagnetic resonance