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We discover magnetic phases hosting highly-elusive and technologically important antiferromagnetic skyrmion quasiparicles in a model for Rashba-coupled Hund's insulator. The results are based on unbiased simulations of a classical superexchange model derived, in this work, from a realistic microscopic electronic Hamiltonian. We also discover a novel skyrmion density wave groundstate characterized by a (Q, Q) modulation in the local skyrmion density map. A unique inhomogeneous state characterized by a circular pattern in spin structure factor and filamentary real-space textures is identified as the parent of sparse antiferromagnetic skyrmions. We predict that the magnetic states reported here can be realized in thin films of multiorbital systems involving 4d or 5d transition metals.

Motivated by the importance of antiferromagnetic skyrmions as building blocks of next-generation data storage and processing devices, we report theoretical and computational analysis of a model for a spin-orbit coupled correlated Hund’s insulator magnet on a triangular lattice. We find that two distinct antiferromagnetic skyrmion crystal (AF-SkX) states can be stabilized at low temperatures in the presence of external magnetic field. The results are obtained via Monte Carlo simulations on an effective magnetic model derived from the microscopic electronic Hamiltonian consisting of Rashba spin-orbit coupling, as well as strong Hund’s coupling of electrons to classical spins at half-filling. The two AF-SkX phases are understood to originate from a classical spin liquid state that exists at low but finite temperatures. These AF-SkX states can be easily distinguished from each other in experiments as they are characterized by peaks at distinct momenta in the spin structure factor which is directly measured in neutron scattering experiments. We also discuss examples of materials where the model as well as the two AF-SkX states can be realized.

An unusual dependence of electrical resistance on the direction of the magnetic field, relative to that of current, in a 2D electron gas with strong spin-orbit coupling formed at the LaVO 3 -KTaO 3 interface is reported. The observations are incompatible with any previously reported magneto-transport measurements. Surprisingly, on the one hand the system exhibits signatures of chiral anomaly such as negative magnetoresistance and planar Hall effect, on the other hand, a number of features are even qualitatively beyond the existing theories. It is found that all the unusual features in transport are controlled by the quantum effects originating from strong spin-orbit coupling induced spin-momentum locking, and the traditional Lorentz mechanism plays a minimal role. The results not only open up a new avenue related to magneto-transport in spin-orbit coupled metals but also pave a path to engineer non-magnetic materials as sensors for vector magnetic fields.