2024/07/06 by Mitsuaki Kawamura, Taisuke Ozaki, Kawamura, Mitsuaki +1
Physics and Astronomy · #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Quantum and electron transport phenomena
paper · pdf · doi:10.48550/arxiv.2407.05091
openalex publication_date 2024/07/06 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present a theory pertaining to the asymptotic behavior of Rashba energy splitting in a quantum-well state (QWS). First, unlike previous studies, we derive k-linear Rashba term from a first-principles Hamiltonian in a physically convincing manner. The k-dependent in-plane intrinsic magnetic-field term originates from the spin--orbit interaction and hybridized s-pz orbital, whereas a steep nucleus potential realizes the linearity for the k of the effective magnetic field. Next, we analyze the Rashba effect of a QWS using a one-dimensional tight-binding model developed based on the bottom-up approach that is aforementioned. The Rashba-splitting behavior of this system is captured from the density at the interface. The density can be expressed analytically as a function of the monolayer number and well depth. Finally, we apply our formula to the QWS of a few-monolayers Ag on an Au(111) surface to validate the theory based on a realistic system. Our tight-binding analysis qualitatively fits the first-principles result using only two fitting parameters and predicts the optimal condition for achieving a large Rashba splitting.