2024/10/21 by Sunny Gupta, Gupta, Sunny, Manoj N. Mattur +3
Materials Science · Physics and Astronomy · #2D Materials and Applications #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Quantum and electron transport phenomena #Topological Materials and Phenomena
paper · pdf · doi:10.48550/arxiv.2410.16242
openalex publication_date 2024/10/21 · openalex created_date 2024/11/06 · openalex updated_date 2026/07/28
Materials with large unidirectional Rashba spin-orbit coupling (SOC), resulting in persistent-spin helix states with small spin-precession length, are critical for advancing spintronics. We demonstrate a design principle achieving it through specific undulations of 2D materials. Analytical model and first-principles calculations reveal that bending-induced asymmetric hybridization brings about and even enhances Rashba SOC. Its strength αR ∝ κ (curvature) and shifting electronic levels Δ∝ κ2. Despite the vanishing integral curvature of typical topographies, implying a net-zero Rashba effect, our two-band analysis and electronic structure calculation of a bent 2D MoTe2 show that only an interplay of αR and Δ modulations results in large unidirectional Rashba SOC with well-isolated states. Their high spin-splitting ∼ 0.16 eV, and attractively small spin-precession length ∼ 1 nm, are among the best known. Our work uncovers major physical effects of undulations on Rashba SOC in 2D materials, opening new avenues for using their topographical deformation for spintronics and quantum computing.