A new theoretical advance enables us to understand how the magnetic properties of a class of magnets called antiferromagnets respond to a magnetic field. The theory describes the magnetic behaviors of both collinear antiferromagnets, in which adjacent magnetic moments point in opposite directions from atom-to-atom, and noncollinear antiferromagnets, where the magnetic moments rotate from one atom to the next. Advantages of this theory include that it is expressed in quantities that are easily measurable and is useful for polycrystalline samples. Applications of the theory to specific compounds illustrate its general utility to understand the properties of antiferromagnets.This theory will help us to understand the interactions between atomic magnets needed for the development of new magnetic materials for such applications as computers, electric motors and other devices that we extensively use in our everyday lives.
Magnetic Susceptibility of Collinear and Noncollinear Heisenberg Antiferromagnets