Noncollinear Ground State from a Four-Spin Chiral Exchange in a Tetrahedral Magnet.

We propose a quartic chiral term m_{x}m_{y}m_{z}∇·m for the energy density of a cubic ferromagnet with broken parity symmetry (point group T_{d}). We demonstrate that this interaction causes a phase transition from a collinear ferromagnetic state to a noncollinear magnetic cone ground state provided its strength exceeds the geometric mean of magnetic exchange and cubic anisotropy. The corresponding noncollinear ground state may also be additionally stabilized by an external magnetic field pointing along certain crystallographic directions.

Publisher's Note: Anomalous Hall Effect in a 2D Rashba Ferromagnet [Phys. Rev. Lett. 117, 046601 (2016)].

This corrects the article DOI: 10.1103/PhysRevLett.117.

Asymmetric and Symmetric Exchange in a Generalized 2D Rashba Ferromagnet.

Dzyaloshinskii-Moriya interaction (DMI) is investigated in a 2D ferromagnet (FM) with spin-orbit interaction of Rashba type at finite temperatures. The FM is described in the continuum limit by an effective s-d model with arbitrary dependence of spin-orbit coupling (SOC) and kinetic energy of itinerant electrons on the absolute value of momentum. In the limit of weak SOC, we derive a general expression for the DMI constant D from a microscopic analysis of the electronic grand potential.

Theory of the Interfacial Dzyaloshinskii-Moriya Interaction in Rashba Antiferromagnets.

In antiferromagnetic (AFM) thin films, broken inversion symmetry or coupling to adjacent heavy metals can induce Dzyaloshinskii-Moriya (DM) interactions. Knowledge of the DM parameters is essential for understanding and designing exotic spin structures, such as hedgehog Skyrmions and chiral Néel walls, which are attractive for use in novel information storage technologies. We introduce a framework for computing the DM interaction in two-dimensional Rashba antiferromagnets.

Anomalous Hall Effect in a 2D Rashba Ferromagnet.

Skew scattering on rare impurity configurations is shown to dominate the anomalous Hall effect in a 2D Rashba ferromagnet. The mechanism originates in scattering on rare impurity pairs separated by distances of the order of the Fermi wavelength. The corresponding theoretical description goes beyond the conventional noncrossing approximation.