What is dzyaloshinskii-moriya interaction?

The Dzyaloshinskii-Moriya interaction (DMI) is a type of spin-orbit coupling in magnetic materials. It was first proposed by I. Dzyaloshinskii in 1958 and later generalized by T. Moriya in 1960.

The DMI arises due to the lack of inversion symmetry in a crystal lattice, which leads to a spin-orbit coupling that can cause an antisymmetric exchange interaction between neighboring spins. In other words, the DMI causes a preference for the spins to align in a particular direction perpendicular to the plane of the magnetic material, breaking the symmetry of the ferromagnetic state.

The DMI is an important parameter that affects the behavior of magnetic materials, particularly in thin films and multilayer structures. It can lead to the formation of chiral magnetic domains, where the magnetization is twisted in a helical or cycloidal pattern. This effect is referred to as DMI-induced chiral symmetry breaking.

The DMI is also important for spintronic applications, as it can be used to manipulate and control the spin torques that drive domain wall motion and spin current generation. Several experimental techniques have been developed to measure the DMI in different materials, including X-ray magnetic circular dichroism, transmission electron microscopy, and magnetic force microscopy.