  Janus particles have attracted significant interest as building blocks for
complex materials in recent years. Furthermore, capillary interactions have
been identified as a promising tool for directed self-assembly of particles at
fluid-fluid interfaces. In this paper, we develop theoretical models describing
the behaviour of magnetic Janus particles adsorbed at fluid-fluid interfaces
interacting with an external magnetic field. Using numerical simulations, we
test the models predictions and show that the magnetic Janus particles deform
the interface in a dipolar manner. We suggest how to utilise the resulting
dipolar capillary interactions to assemble particles at a fluid-fluid
interface, and further demonstrate that the strength of these interactions can
be tuned by altering the external field strength, opening up the possibility to
create novel, reconfigurable materials.
