Fractional electrical dimensionality in the spin solid phase of artificial honeycomb lattice

Abstract

Two-dimensional artificial magnetic honeycomb lattices are at the forefront of research on unconventional magnetic materials. Among the many emergent magnetic phases that are predicted to arise as a function of temperature, the low temperature spin solid phase with zero magnetization and entropy is of special importance. Here, we report an interesting perspective to the consequence of spin solid order in an artificial honeycomb lattice of ultra-small connected elements using electrical dimensionality analysis. At low temperature, T ≤ 30 K, the system exhibits a very strong insulating characteristic. The electrical dimensionality analysis of the experimental data reveals a fractional dimensionality of d = 0.6(0.04) in the spin solid phase of honeycomb lattice at low temperature. The much smaller electrical dimension in the spin solid phase, perhaps, underscores the strong insulating behavior in this system. Also, the fractional dimensionality in an otherwise two-dimensional system suggests a non-surface-like electrical transport at low temperature in an artificial honeycomb lattice.