Physical Review Letters

Origin of the geometric forces accompanying Berry’s geometric potentials

Yakir Aharonov, Ady Stern

Published Dec 21, 1992• 124 citations

Abstract

We consider the dynamics of a particle carrying a magnetic moment in a strong magnetic field whose direction varies slowly in space. In particular, we discuss the geometric Lorentz-type and electric-type forces that were discovered in studies of Berry's phase. We show that the Lorentz-type force felt by the particle is caused by a small misalignment of the magnetic moment with respect to the magnetic field while the electric-type force is the time average of a strong oscillatory force induced by the precession of the magnetic moment.

DOI: 10.1103/physrevlett.69.3593

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