Symmetry-designed BiFeO3 single domain spin cycloid for efficient spintronics

TL;DR

This paper demonstrates how anisotropic in-plane strain stabilizes a single antiferromagnetic domain with a unique spin cycloid in BiFeO3 films, enabling efficient and reproducible control of multiferroic properties for spintronics.

Contribution

The study introduces a method to stabilize a single antiferromagnetic domain in BiFeO3 using anisotropic strain, overcoming previous challenges of multi-domain states and ferroelectric fatigue.

Findings

Stable single antiferromagnetic domain achieved

Deterministic 180° switching over 1,000 cycles

Enhanced magnon transport in monodomain films

Abstract

Deterministic control of coupled ferroelectric and antiferromagnetic orders remains a central challenge in multiferroics, limiting their integration into functional magnetoelectrics and magnonic-devices. (111)pc BiFeO3 with a robust single spin cycloid, offers direct magnetoelectric-coupling and a platform for efficient spin transport, yet multi-magnetic domains and ferroelectric-fatigue have prevented reproducible control. Here, we show that anisotropic-compressive in-plane strain stabilizes a single antiferromagnetic domain with unique spin-cycloid vector, by breaking the symmetry of the (111)pc plane. Epitaxial BiFeO3 films grown on orthorhombic NdGaO3 (011)o [(111)pc] substrates impose the required anisotropic in-plane strain and stabilizes single antiferromagnetic domain, as confirmed through direct imaging with scanning NV microscopy and non-resonant-x-ray-magnetic-scattering. Remarkably, these engineered films exhibit deterministic and non-volatile 180{\deg} switching of ferroelectric and single antiferromagnetic domains over 1,000 cycles. The monodomain state also enables anisotropic and threefold enhanced magnon transport with reduced scattering. Thus, symmetry-designed (111)pc monodomain BiFeO3 offers a robust platform for advanced magnetoelectric and magnonic applications.