Microscopic theory of flexo Dzyaloshinskii-Moriya-type interaction

Abstract

We study interaction between two magnetic impurities mediated by itinerant electrons on the surface of curved magnets based on perturbation theory. We show that Dzyaloshinskii-Moriya type interaction can arise from inhomogeneous spin texture by bending, without any spin-orbit coupling. Analytical expressions of the Dzyaloshinskii-Moriya type interaction are obtained. We demonstrate this effect in a one-dimensional ring model.

Figures (4)

• Figure 1: Uniform magnetization (a) can be made inhomogeneous by bending (b). Two magnetic impurities (red arrows) are placed on the surface of a bent magnet and interact with each other via itinerant electrons.
• Figure 2: The diagrammatic representations of the free energy to first order in $H_2$. Solid, wavy and dotted lines represent electron Green's function, $H_1$ and $H_2$, respectively.
• Figure 3: The diagrammatic representations of the free energy to secont order in $H_2$. Solid, wavy and dotted lines represent electron Green's function, $H_1$ and $H_2$, respectively.
• Figure 4: $F(\theta_{21}, T, E_F)$ as a function of $\theta_{21}$ for $E_F/E_R=100$ with (a) $T/E_R=0.25$ and (b) 2.5.