Correlating the Strain Distribution and Magnetic Texture in a Layered Chiral Magnet

Quasi two dimensional (quasi 2D) materials host mechanical, electrical, and magnetic properties useful for novel microelectronic devices. Of particular interest are quasi-2D chiral magnets which are a much desired platform for new topological spin structures and related transport phenomena. These properties can be directly affected by the lattice degrees of freedom such as interlayer spacing and in plane strain and shear and are often spatially inhomogeneous. Therefore, mapping and understanding the mechanical strain inherent or induced in quasi 2D materials accurately is critical to enhancing their functionality in devices.

We focus on the distribution of strain and sheer in an intercalated transition metal dichalcogenide (TMD) Cr_1/3TaS₂. Recent work on Cr_1/3TaS₂ demonstrated emergent spiral magnetic superstructures that can be directly affected by both the shear strain and the application of an external field as low as 100 Oe. Despite these observations, a connection between the magnetic spin and the lattice is yet to be experimentally explored.

We performed scanning coherent x-ray nanodiffraction (CXNRD) measurements of exfoliated Cr_1/3TaS₂ thin flakes and recorded diffraction patterns from a grid of scanned locations at a series of tilting angles across the Bragg peak. We collected five dimensional CXNRD dataset that was transformed into the intensity distribution in reciprocal space around the lattice vector at each probed location and used it to spatially resolved the distribution of ε_yz and ε_zx the leading terms of the strain tensor. We further use the distribution of strain to reconstruct the distribution of magnetic spin texture consistent with previous magnetic force microscopy (MFM) studies. Our work thus opens the way for future manipulations of magnetic textures and domains through the lattice degree of freedom.