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Potential energy of a magnetised body in an external magnetic field
Zeeman energy, or the external field energy, is the potential energy of a magnetised body in an external magnetic field. It is named after the Dutch physicist Pieter Zeeman, primarily known for the Zeeman effect. In SI units, it is given by
where HExt is the external field, M the local magnetisation, and the integral is done over the volume of the body. This is the statistical average (over a
unit volume macroscopic sample) of a corresponding microscopic Hamiltonial (energy) for each individual magnetic momentm, which is however experiencing a local induction B:
References
F. Barozzi, F. Gasparini, Fondamenti di Elettrotecnica: Elettromagnetismo, UTET Torino, 1989
Hubert, A. and Schäfer, R. Magnetic domains: the analysis of magnetic microstructures, Springer-Verlag, 1998