Eur. Phys. J. Special Topics 227, 2439–2454 (2019)
https://doi.org/10.1140/epjst/e2019-700016-5

Regular Article

Magnetic tweezers for captive disclination loops

¹ CENIMAT, Faculdade de Ciências e Tecnologia - Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
² Laboratoire de Physique des Solides, Université Paris-Sud, Bât. 510, 91405 Orsay, France

^a e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Received: 17 May 2017
Received in final form: 28 September 2017
Published online: 28 March 2019

Abstract

Disclination loops threaded on a polymeric fiber with planar axial anchoring are shown to be sensitive to magnetic fields. In particular, a homogeneous magnetic field oblique to the fiber drives translation of disclination loops along it. The velocity of translation depends on the intensity of the field and on the angle between the field and the fiber. It is shown experimentally that an inhomogeneous magnetic field of an appropriate geometry can act as a trap for disclination loops. When such a magnetic trap is translated along the fiber, it drags the loop with it and therefore acts as magnetic tweezers. Theoretical model of the translational stability of disclination loops in magnetic fields is proposed.