  When two magnetic skyrmions - whirl-like, topologically protected
quasiparticles - form a bound pair, a biskyrmion state with a topological
charge of $N_\mathrm{Sk}=\pm 2$ is constituted. Recently, especially the case
of two partially overlapping skyrmions has brought about great research
interest. Since for its formation the individual skyrmions need to posses
opposite in-plane magnetizations, such a biskyrmion cannot be stabilized by the
Dzyaloshinskii-Moriya-interaction (DMI), which is the interaction that
typically stabilizes skyrmions in non-centrosymmetric materials and at
interfaces. Here, we show that these biskyrmions can be stabilized by the
dipole-dipole interaction in centrosymmetric materials in which the DMI is
forbidden. Analytical considerations indicate that the bound state of a
biskyrmion is energetically preferable over two individual skyrmions. As a
result, when starting from two skyrmions in a micromagnetic simulation, a
biskyrmion is formed upon relaxation. We propose a scheme that allows to
control this biskyrmion formation in nanodisks and analyze the individual
steps.
