  In this work, and by means of micromagnetic simulations, we study the
magnetic properties of toroidal nanomagnets. The magnetization ground state for
different values of the aspect ratio between the toroidal and polar radii of
the nanotorus has been obtained. The hysteresis curves are also obtained,
evidencing the existence of two reversal modes depending on the geometry: a
vortex mode and a coherent rotation. A comparison between toroidal and
cylindrical nanoparticles has been performed evidencing that nanotori can
accommodate a vortex as the ground state for smaller volume than cylindrical
nanorings. This is important because if vortices are used as bits of
information, nanotori allow a higher density data storage.
