The magnetic equivalent of electricity, dubbed "magnetricity", has been demonstrated experimentally for the first time. Just as the flow of electrons produces electrical current, individual north and south magnetic poles have been observed to roam freely, generating magnetic "current".

The result could lead to the development of "magnetronics", including nano-scale computer memory.

The individual atoms would still have both north and south poles. But patterns in their orientation would propagate through the material and look just like little magnetic poles roaming around (see illustration). These patterns would effectively be monopoles, as far as any measurements are concerned.

In September, two teams of physicists fired neutrons at spin ices made of titanium-containing compounds chilled close to absolute zero. The behaviour of the neutrons suggested that monopoles were present in the material.

Now, another team has managed to measure the amount of magnetic "charge" on the monopoles and to measure magnetic analogues to electric current for the first time. The team calls the motion and interaction of monopoles "magnetricity".

The experiment, 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. NewScientist