Antichiral order and spin reorientation transitions of triangle-based antiferromagnets

Antiferromagnetically coupled spins on a triangle tend to order at 120\ifmmode^\circ\else\textdegree\fi{} angles to one another. When confined to a plane, the pattern is antichiral if the spins rotate counterclockwise while traversing the triangle clockwise. The author shows that in this situation spin reorientation transitions generically occur as an applied field is increased, with spins rotating in the same/opposite sense as the field for high/low fields. The complex spin evolution provides tunability for magnetic and spintronic applications.