We have imaged magnetization textures of permalloy films patterned into Penrose P2 tilings (P2T) using scanning electron microscopy with polarization analysis (SEMPA). P2T film segments have near-uniform, bipolar magnetization, similar to artificial spin ices, but with asymmetric vertex coordination that induces a more complex spin ice behavior mediated by exchange interactions in vertex domain walls. Numerical simulations including long-range dipole interactions agree with SEMPA images of as-grown P2T, and predict a ferromagnetic ground state for a 2D P2T lattice of classical Ising spins.
@article{arxiv.1501.02760,
title = {Direct Imaging of Complex Spin Ice Behavior and Ordered Sublattices in Artificial Ferromagnetic Quasicrystals},
author = {V. S. Bhat and A. Balk and B. Farmer and E. Teipel and N. Smith and J. Unguris and J. T. Hastings and L. E. De Long},
journal= {arXiv preprint arXiv:1501.02760},
year = {2015}
}
Comments
8 pages, 4 figures; submitted to Physical Review Letters, December 30, 2014