A Skyrmion is a topological configuration in which local spins wrap around the unit sphere for an integer number of times. After decades of theoretical discussions in high energy physics, it has been recently observed in a series of non-centrosymmetric chiral magnets. Several experiments by neutron scattering or transmission electron microscopy confirm the presence of skyrmions in a crystalline state at a finite window of magnetic field and temperature. Skyrmions show various novel properties inherent to its topological nature, such as topological Hall effect, topological stability, and ultralow critical current for movement, which offer the skyrmion promising prospects for next generation spintronic devices and information storage.
In this talk, I will explain the physical origin of skyrmions in chiral magnets, and discuss their dynamics under electric current or temperature gradient, where an emergent electromagnetism plays an important role. Furthermore, several routes to single skyrmions will be presented, and new chiral magnet materials are discussed.