Uniaxial Néel vector control in perovskite oxide thin films by anisotropic strain engineering

Antiferromagnetic (AF) thin films typically exhibit a multidomain state, and control of the AF N\'eel vector is challenging, as AF materials are robust to magnetic perturbations. In this paper, uniaxial N\'eel vector control is demonstrated by relying on anisotropic strain engineering of epitaxial thin films of the prototypical AF material ${\mathrm{LaFeO}}_{3}$ (LFO). Orthorhombic (011)- and (101)-oriented ${\mathrm{DyScO}}_{3}$, ${\mathrm{GdScO}}_{3}$, and ${\mathrm{NdGaO}}_{3}$ substrates are used to engineer different anisotropic in-plane strain states. The anisotropic in-plane strain stabilizes structurally monodomain monoclinic LFO thin films. The uniaxial N\'eel vector is found along the tensile strained $b$ axis, contrary to bulk LFO 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 AF materials for mesoscopic device technology.