Uniaxial N\'eel Vector Control in Perovskite Oxide Thin Films by Anisotropic Strain Engineering

TL;DR

This paper demonstrates that anisotropic in-plane strain engineering in epitaxial LaFeO3 thin films can control the Ne9el vector direction, stabilizing monodomain states and enabling new functionalities for antiferromagnetic device applications.

Contribution

The study introduces a method to control the Ne9el vector in antiferromagnetic thin films via anisotropic strain, achieving uniaxial control and monodomain states in LaFeO3.

Findings

Uniaxial Ne9el vector aligned along tensile strained b axis.

Monodomain LaFeO3 thin films stabilized by anisotropic strain.

No magnetic domains observed in strained films.

Abstract

Antiferromagnetic thin films typically exhibit a multi-domain state, and control of the antiferromagnetic N\'eel vector is challenging as antiferromagnetic materials are robust to magnetic perturbations. By relying on anisotropic in-plane strain engineering of epitaxial thin films of the prototypical antiferromagnetic material LaFeO3, uniaxial N\'eel vector control is demonstrated. Orthorhombic (011)- and (101)-oriented DyScO3, GdScO3 and NdGaO3 substrates are used to engineer different anisotropic in-plane strain states. The anisotropic in-plane strain stabilises structurally monodomain monoclinic LaFeO3 thin films. The uniaxial N\'eel vector is found along the tensile strained b axis, contrary to bulk LaFeO3 having the N\'eel vector along the shorter a axis, and no magnetic domains are found. Hence, anisotropic strain engineering is a viable tool for designing unique functional responses, further enabling antiferromagnetic materials for mesoscopic device technology.