  We investigate skyrmion configuration and dynamics in antiferromagnetic thin
disks. It is shown that the skyrmion acquires oscillatory dynamics with
well-defined amplitude and frequency which may be controlled on demand by the
spin-polarized current. Such dynamics are robust in the sense that an interface
between two half-disks cannot change the dynamics appreciably. Indeed, the
skyrmion keeps its oscillatory despite crossing this interface. The way
skyrmion found to do that is by modifying its core region shape so that its
total energy is unaltered for several cycles.
