Topological Surface Magnetism and Neel Vector Control in a Magnetoelectric Antiferromagnet

Abstract

Antiferromagnetic states with no stray magnetic fields can enable high-density ultra-fast spintronic technologies. However, the detection and control of antiferromagnetic Neel vectors remain challenging. Linear magnetoelectric antiferromagnets (LMAs) may provide new pathways, but applying simultaneous electric and magnetic fields, necessary to control Neel vectors in LMAs, is cumbersome and impractical for most applications. Herein, we show that Cr2O3, a prototypical room-temperature LMA, carries a topologically-protected surface magnetism in all surfaces, which stems from intrinsic surface electric fields due to band bending, combined with the bulk linear magnetoelectricity. Consequently, bulk Neel vectors with zero bulk magnetization can be simply tuned by magnetic fields through controlling the magnetizations associated with the surface magnetism. Our results imply that the surface magnetizations discovered in Cr2O3 should be also present in all LMAs.

References in corpus (13)

• Antiferromagnetic spintronics
• New Perspectives for Rashba Spin-Orbit Coupling
• Electrical switching of an antiferromagnet
• Room-temperature antiferromagnetic memory resistor
• Robust isothermal electric switching of interface magnetization: A route to voltage-controlled spintronics
• Antiferromagnetic opto-spintronics: Part of a collection of reviews on antiferromagnetic spintronics
• Purely Antiferromagnetic Magnetoelectric Random Access Memory
• Electric-Field-Controlled Antiferromagnetic Spintronic Devices
• Equilibrium magnetization at the boundary of a magnetoelectric antiferromagnet
• Nanoscale mechanics of antiferromagnetic domain walls
• Relativistic nature of a magnetoelectric modulus of Cr_2O_3-crystals: a new 4-dimensional pseudoscalar and its measurement
• Co-existence of Bloch and Neel walls in a collinear antiferromagnet
• Low-energy magnetoelectric control of domain states in exchange-coupled heterostructures

Cited by in corpus (5)

• Surface Magnetization in Antiferromagnets: Classification, example materials, and relation to magnetoelectric responses
• Surface-symmetry-driven Dzyaloshinskii--Moriya interaction and canted ferrimagnetism in collinear magnetoelectric antiferromagnet Cr${}_2$O${}_3$
• Trompe L'oeil Ferromagnetism: magnetic point group analysis
• Magnetic structure and magnetoelectric coupling in antiferromagnet Co5(TeO3)4Cl2
• Linear magnetoelectricity in the Zintl phase pnictides (Ba, Ca, Sr)${\mathrm{Mn}}_2{(\mathrm{P},\mathrm{As},\mathrm{Sb})}_2$ from first principles calculations