Magnetic Monopole Dynamics in Artificial Kagome Ice

Using Lorentz-force TEM, we have directly observed the existence of magnetic monopoles in artificial kagome ice, as have been recently seen in the rare-earth titanate spin ices [1]. Monopoles arise in this system from the unique geometrical interactions that result~from~nanoscale patterning of a NiFe thin film. The monopoles act as independent magnetic charges, free to move through the kagome lattice. We will present empirical guidelines for the monopole dynamics and make connections with relevant theories.\\[4pt] [1] C. Castelnovo, R. Moessner, and S. L. Sondhi, Nature \textbf{451}, 42 (2008).