Noncollinear magnetic structure in U₂Pd₂In at high magnetic fields

We report an unexpected magnetic-field-driven magnetic structure in the 5 f -electron Shastry-Sutherland system U₂Pd₂In. This phase develops at low temperatures from a noncollinear antiferromagnetic ground state above the critical field of 25.8 T applied along the a axis. All U moments have a net magnetic Moment in the direction of the applied field, described by a ferromagnetic propagation vector q_F = (0 0 0) and an antiferromagnetic component described by a propagation vector q_AF = (0 0.30 1/2 ) due to a modulation in the direction perpendicular to the applied field. We conclude that this surprising noncollinear magnetic structure is due to a competition between the single-ion anisotropy trying to keep moments, similar to the ground state, along the [110]-type directions, Dzyaloshinskii-Moryia interaction forcing them to be perpendicular to each other and application of the external magnetic field attempting to align them along the field direction.