The magnetic susceptibility of a material quantifies how much the material is magnetized when exposed to a magnetic field. This macroscopic property results from the contributions of many microscopic quantum states with nonzero magnetic moments. A typical susceptibility measurement, however, yields a value that averages over the statistical ensemble of all states—it cannot deliver information on the populations of specific quantum states. Now, a team at Cardiff University and University College London, both in the UK, shows that, in a particular magnetic system, a susceptibility measurement can directly probe the populations of two spin states . The idea could allow researchers to use simple susceptibility measurements to study the quantum-state dynamics of exotic magnetic materials.
To read more, click here.