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arXiv · 1612.08003

Defect Dynamics in Artificial Colloidal Ice: Real-Time Observation, Manipulation and Logic Gate

Johannes Loehr·Antonio Ortiz-Ambriz·Pietro Tierno
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Abstract

We study the defect dynamics in a colloidal spin ice system realized by filling a square lattice of topographic double well islands with repulsively interacting magnetic colloids. We focus on the contraction of defects in the ground state, and contraction/expansion in a metastable biased state. Combining real-time experiments with simulations, we prove that these defects behave like emergent topological monopoles obeying a Coulomb law with an additional line tension. We further show how to realize a completely resettable "NOR" gate, which provides guidelines for fabrication of nanoscale logic devices based on the motion of topological magnetic monopoles.

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Johannes Loehr, Antonio Ortiz-Ambriz, Pietro Tierno. 2016-12-23. Defect Dynamics in Artificial Colloidal Ice: Real-Time Observation, Manipulation and Logic Gate. https://doi.org/10.1103/physrevlett.117.168001

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