  The magnetic field-driven evolution of chiral spin textures in thin
helimagnet nanodisk with varied size are investigated by means of Monte Carlo
simulation. It is demonstrated that the complex spin texture may simply be
regarded as the superposition of the edged state with in plane spin orientation
perpendicular or parallel to the edge and the bulk state with the features
similar to two-dimensional chiral magnetic films. With the increase of the
external field, the proportion of the parallel spins of the edge state
increases, and the spin textures finally transfers into edged magnetic vortex.
The arrangement of skyrmions strongly depends on the disk size. In addition,
the uniaxial anisotropy and dipolar coupling in certain ranges are able to
stabilize a special magnetic vortex with Skyrmionic core while the disk size is
comparable with the wavelength of helix state.
