There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.
Abstract
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 the ones with fractional
electric charge e/3 in quantum Hall physics. Here we propose that magnetic monopoles
emerge in a class of exotic magnets known collectively as spin ice: the dipole moment
of the underlying electronic degrees of freedom fractionalises into monopoles. This
would account for a mysterious phase transition observed experimentally in spin ice
in a magnetic field, which is a liquid-gas transition of the magnetic monopoles. These
monopoles can also be detected by other means, for example, in an experiment modelled
after the Stanford magnetic monopole search.