Long-Range Self-Ordering of Micropillar Arrays

초록

Artificial swarming motion has been researched by controlling long-range magnetic interactions between dipolar magnetic particles. Though magnetic ordering has advantages with unharmful property and fast response time, the self-ordering is not reversibly implemented because a location of magnetic particles is not fixed with a liquid medium. Alternatively, we devise periodically arranged micropillar arrays composed of magnetic particles and elastomeric polymer matrix for reversible and stepwise self-ordering. Under contactless magnetic field, independently separated micropillars undergo an increase of magnetization value, operating as micromagnets. Adjacent pillar tops attract in pair while the pillar bases are still fixed to the substrates. As magnetic flux density continuously increases, long-range connectivity of pillar tops is finally achieved through stepwise self-organization. We will discuss influence of geometry form factors including interpillar spacing, pillar height, and anisotropic cross-sections of the micropillars on the stepwise self-organization.