Magnetic monopoles in spin ice

@article{Castelnovo2008MagneticMI,
  title={Magnetic monopoles in spin ice},
  author={Claudio Castelnovo and Roderich Moessner and S. L. Sondhi},
  journal={Nature},
  year={2008},
  volume={451},
  pages={42-45}
}
Electrically charged particles, such as the electron, are ubiquitous. In contrast, no elementary particles with a net magnetic charge have ever been observed, despite intensive and prolonged searches (see ref. 1 for example). We pursue an alternative strategy, namely that of realizing them not as elementary but rather as emergent particles—that is, as manifestations of the correlations present in a strongly interacting many-body system. The most prominent examples of emergent quasiparticles are… 

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