There has been tremendous interest in manipulating electron and hole spin states in low-dimensional structures for electronic and spintronic applications. By first-principles calculations we study the edge magnetic anisotropy and exchange coupling in zigzag nanoribbons of stanene, a graphenelike honeycomb material with strong spin-orbit coupling. We find that the zigzag stanene nanoribbon is always insulating and its band gap depends on the magnetization direction and the interedge magnetic coupling. Moreover, we propose a strategy whereby both the magnetic anisotropy and the exchange coupling are controlled by electron and hole doping, demonstrating an experimentally feasible gate-induced modulation of the magnetization. Another interesting finding is that for distinct magnetizations, spin or valley degeneracies are broken under the action of the spin-orbit coupling and further tuned by a transverse electric field, giving full play to spin and valley degrees of freedom. These intriguing features offer a practical avenue for designing energy-efficient devices based on magnetoelectric couplings and multiple electronic degrees of freedom.

• Received 4 August 2017
• Revised 6 June 2018

DOI:https://doi.org/10.1103/PhysRevApplied.10.034048