Coulomb physics in spin ice, from magnetic monopoles to magnetic currents

It was proposed that spin ice, a class of rare earth titanates, hosts elementary excitations akin to magnetic monopoles. Recently, Bramwell and co-workers [arXiv:arXiv:0907.0956] measured the Wien effect in Dy2Ti2O7, directly probing the nature of these monopoles and making dysprosium titanate the first example of a magnetolyte.