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arXiv · 2012.06324

Dirac imprints on the $g$-factor anisotropy in graphene

Marta Prada·Lars Tiemann·Jonas Sichau·Robert H Blick
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Abstract

Dirac electrons in graphene are to lowest order spin 1/2 particles, owing to the orbital symmetries at the Fermi level. However, anisotropic corrections in the $g$-factor appear due to the intricate spin-valley-orbit coupling of chiral electrons. We resolve experimentally the $g$-factor along the three orthogonal directions in a large-scale graphene sample. We employ a Hall bar structure with an external magnetic field of arbitrary direction, and extract the effective $g$-tensor via resistively-detected electron spin resonance. We employ a theoretical perturbative approach to identify the intrinsic and extrinsic spin orbit coupling and obtain a fundamental parameter inherent to the atomic structure of $^{12}$C, commonly used in ab-initio models.

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Marta Prada, Lars Tiemann, Jonas Sichau, Robert H Blick. 2020-12-11. Dirac imprints on the $g$-factor anisotropy in graphene. https://doi.org/10.1103/physrevb.104.075401

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