Magnetostatic interactions between magnetic nanotubes
  The investigation of interactions between magnetic nanotubes is complex and often involves substantial simplifications. In this letter an analytical expression for the magnetostatic interaction, taking into account the geometry of the tubes, has been obtained. This expression allows for the definition of a critical vertical separation for relative magnetization between nanotubes and can be used for tailoring barcode-type nanostructures with prospective applications such as biological separation and transport. 
J. Escrig, S. Allende, D. Altbir, M. Bahiana
cond-mat.mes-hall cond-mat.mtrl-sci