Magnetic charge behaving as electric charge for the first time

The research at London Centre for Nanotechnology find prove for the existence of atom-sized magnetic charges called ‘magnetic monopoles’. These monopoles behave and interact just like more familiar electric charges.Research also demonstrates a perfect symmetry between electricity and magnetism – a phenomenon dubbed ‘magnetricity'.

In order to prove experimentally the existence of magnetic current for the first time, the research team mapped Onsager's 1934 theory of the movement of ions in water onto magnetic currents in a material called spin ice. They then tested the theory by applying a magnetic field to a spin ice sample at a very low temperature and observing the process using muon relaxation at ISIS, a technique which acts as a super microscope allowing researchers to understand the world around us at the atomic level.

The experiment allowed the team to detect magnetic charges in the spin ice (Dy2Ti2O7), to measure their currents, and to determine the elementary unit of the magnetic charge in the material. The monopoles they observed arise as disturbances of the magnetic state of the spin ice, and can exist only inside the material.

This research, reported in Nature, was led by Steven Bramwell of the London Centre for Nanotechnology in the UK. Bramwell was a member of a team, led by Tom Fennell of the Laue-Langevin Institute in Grenoble, that reported neutron results in September.