CP 2 skyrmions and skyrmion crystals in realistic quantum magnets.

Magnetic skyrmions are nanoscale topological textures that have been recently observed in different families of quantum magnets. These objects are called CP 1 skyrmions because they are built from dipoles-the target manifold is the 1D complex projective space, CP 1  ≅ S 2 . Here we report the emergence of magnetic CP 2 skyrmions in a realistic spin-1 model, which includes both dipole and quadrupole moments. Unlike CP 1 skyrmions, CP 2 skyrmions can also arise as metastable textures of quantum paramagnets, opening a new road to discover emergent topological solitons in non-magnetic materials. The quantum phase diagram of the spin-1 model also includes magnetic field-induced CP 2 skyrmion crystals that can be detected with regular momentum- (diffraction) and real-space (Lorentz transmission electron microscopy) experimental techniques.