It has been suggested that the anisotropic behavior of orbital transport can be distinct from that of the spin counterpart. On another front, the microscopic mechanisms underlying the anomalous Hall effect and the spin Hall effect are generally categorized into the intrinsic Berry curvature mechanism and the extrinsic mechanism induced by disorder scattering, each with distinct scaling relations. A similar analysis for orbital transport has rarely been performed. Here, we investigate both aspects of the orbital current generation in a light metal V. The orbital-to-spin conversion is achieved using a heavy metal Pt insertion layer or Ni as the ferromagnetic layer. Benefiting from the epitaxial growth of V with a low disorder strength, the orbital current generation is characterized by a large transverse conductivity and long diffusion length, consistent with the expectation for an intrinsic orbital Hall effect. Across all the heterostructures studied, we confirm the orbital current's isotropic nature, i.e., the orbital current generation is barely affected when the charge current is applied along different crystallographic directions, consistent with the high-symmetry crystal structure. Crucially, the intrinsic nature of the orbital current generation is demonstrated by the scaling analysis, showing a scattering-independent orbital Hall conductivity.

Close

PrevNext

View figure in article

• Spin orbitronics
• Spin-orbit torque
• Elemental metals
• Ferromagnetic resonance