Domain structures and magnetic ice-order in NiFe nano-network with honeycomb structure

The magnetic domain configurations and the magnetization processes in a permalloy wire-based honeycomb nano-network have been investigated by means of magnetic-force microscopy and magnetoresistance measurement. The magnetic structure is mainly governed by the magnetic interaction among the magnetic pole on the vertices, being similar to the so-called "ice-rule." The magnetization vector in a wire behaves coherently. The present results seem to give a direct analogy between the honeycomb network and an Ising system on a kagoḿ lattice. The ice-rule type interaction, however, disappears with reducing magnetic energy at the vertices.