Electric control of the edge magnetization in zigzag stanene nanoribbon

TL;DR

This paper demonstrates how electric fields and doping can control edge magnetization and spin-valley properties in zigzag stanene nanoribbons, enabling tunable spintronic and valleytronic device functionalities.

Contribution

It reveals the electric control of edge magnetization, magnetic anisotropy, and spin-valley coupling in stanene nanoribbons through first-principles calculations, highlighting potential for energy-efficient spintronic devices.

Findings

Edge magnetization can be tuned by electric fields and doping.

Magnetic order and anisotropy are controllable via electron/hole doping.

Valley degeneracy is adjustable with transverse electric fields.

Abstract

There has been tremendous interest in manipulating electron and hole-spin states in low-dimensional structures for electronic and spintronic applications. We study the edge magnetic coupling and anisotropy in zigzag stanene nanoribbons, by first-principles calculations. Taking into account considerable spin-orbit coupling and ferromagnetism at each edge, zigzag stanene nanoribbon is insulating and its band gap depends on the inter-edge magnetic coupling and the magnetization direction. Especially for nanoribbon edges with out-of-plane antiferromagnetic coupling, two non-degenerate valleys of edge states emerge and the spin degeneracy is tunable by a transverse electric field, which give full play to spin and valley degrees of freedom. More importantly, both the magnetic order and anisotropy can be selectively controlled by electron and hole doping, demonstrating a readily accessible gate-induced modulation of magnetism. These intriguing features offer a practical avenue for designing energy-efficient devices based on multiple degrees of freedom of electron and magneto-electric couplings.