Title: Magnetic diode at $T$ = 300 K,
Abstract: We report the finding of unidirectional electronic properties, analogous to a
semiconductor diode, in two-dimensional artificial permalloy honeycomb lattice
of ultra-small bond, with a typical length of ~ 12 nm. The unidirectional
transport behavior, characterized by the asymmetric colossal enhancement in
differential conductivity at a modest current application of ~ 10-15 $\mu$A,
persists to T = 300 K in honeycomb lattice of thickness ~ 6 nm. The asymmetric
behavior arises without the application of magnetic field. A qualitative
analysis of experimental data suggests the role of magnetic charge or monopoles
in the unusual observations with strong implication for spintronics.