Magnetoresistance Study of Kagome Artificial Spin Ice with Fibonacci Distortions

Nanofabrication techniques allow magnetic thin films to be lithographically patterned into arrays of interacting macro-spins designed to exhibit emergent physical properties. We study the effects of continuous symmetry breaking on the magnetoresistive behavior of frustrated Kagome (alt. honeycomb) ASI whose periodic lattice is aperiodically distorted by repeated application of a substitution algorithm: A Fibonacci sequence of binary digits is mapped into short (d1) and long (d2) primitive lattice translations, which alters the magnetic moments and angular coordination of the three-fold Kagome vertices. Kagome arrays with variable distortions are patterned in series to permit simultaneous longitudinal and transverse magnetoresistances measurements in external magnetic fields. The direction and magnitude of applied field was varied to produce distinct, interesting differences in the magnetoresistance response of the distorted Kagome arrays, compared to the undistorted arrays.