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Updated: Aug 19, 2026

Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Nonquantized dirac monopoles and strings in the berry phase of anisotropic spin systems
1Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany. bruno@mpi-halle.de
Abstract:
The Berry phase of an anisotropic spin system that is adiabatically rotated along a closed circuit C is investigated. It is shown that the Berry phase consists of two contributions: (i) a geometric contribution which can be interpreted as the flux through C of a nonquantized Dirac monopole, and (ii) a topological contribution which can be interpreted as the flux through C of a Dirac string carrying a nonquantized flux, i.e., a spin analogue of the Aharonov-Bohm effect. Various experimental consequences of this novel effect are discussed.
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