In this work, we explore a kind of geometrical effect in the thermodynamics of artificial spin ices (ASI). In general, such artificial materials are athermal. Here, We demonstrate that geometrically driven dynamics in ASI can open up the panorama of exploring distinct ground states and thermally magnetic monopole excitations. It is shown that a particular ASI lattice will provide a richer thermodynamics with nanomagnet spins experiencing less restriction to flip precisely in a kind of rhombic lattice. This can be observed by analysis of only three types of rectangular artificial spin ices (RASI). Denoting the horizontal and vertical lattice spacings by a and b, respectively, then, a RASI material can be described by its aspect ratio γ ≡ a/b. The rhombic lattice emerges when γ = √ 3. So, by comparing the impact of thermal effects on the spin flips in these three appropriate different RASI arrays, it is possible to find a system very close to the ice regime.

Sets of nanomagnets are often utilized to mimic cellular automata in design of nanomagnetic logic devices or frustration and emergence of magnetic charges in artificial spin ice systems. in previous work we showed that unidirectional arrangement of nanomagnets can behave as artificial spin ice, with frustration arising from second neighbor dipolar interaction, and present good magnetic charge mobility due to the low string tension among charges. Here, we present an experimental investigation of magnetic charge population and mobility in function of lateral and longitudinal distance among nanomagnets. Our results corroborate partially the theoretical predictions, performed elsewhere by emergent interaction model, could be useful in nanomagnet logic devices design and brings new insights about the best design for magnetic charge ballistic transport under low external magnetic field with magnetic charge mobility tunning for application in magnetricity.

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We study planar rectangular-like arrays composed by macroscopic dipoles (magnetic bars with size around a few centimeters) separated by lattice spacings a and b along each direction. Physical behavior of such macroscopic artificial spin ice (MASI) systems are shown to agree much better with theoretical prediction than their micro-or nano-scaled counterparts, making MASI "almost ideal prototypes" for readily naked-eye visualization of geometrical frustration effects.