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arXiv · 2505.24745

Spin-dependent transport through edge states in 2D semi-Dirac materials with Rashba spin-orbit coupling and band inversion

Marta García-Olmos·Yuriko Baba·Alexander López·Mario Amado·Rafael A. Molina
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Abstract

We investigate the bulk-boundary correspondence in two-dimensional type-I semi-Dirac materials with band inversion and Rashba spin-orbit coupling. Employing a dimensional reduction framework, we identify the Zak phase along the quadratically dispersing direction as a topological invariant that captures the presence of edge states. In the non-trivial topological regime, systems with finite width exhibit energy-dependent edge states that are topologically protected only at specific momenta. At kx equal to zero, symmetry-protected edge states emerge, analogous to the Rashba-free case. At finite kx, the interplay of spin-orbit coupling and band structure gives rise to spin-dependent edge states, localized on specific edges based on its spin and particle-hole character. We compute spin-resolved conductance through these edge channels and observe robust, tunable oscillations attributable to spin precession induced by the effective Rashba magnetic field. These results reveal how spin-orbit interactions enrich the edge physics of semi-Dirac systems and provide a platform for spintronic control in anisotropic topological materials.

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Marta García-Olmos, Yuriko Baba, Alexander López, Mario Amado, Rafael A. Molina. 2025-05-30. Spin-dependent transport through edge states in 2D semi-Dirac materials with Rashba spin-orbit coupling and band inversion. https://arxiv.org/abs/2505.24745

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