Control of vortex chirality in Ni80Fe20 dots using dipole coupled nanomagnets

A magnetic vortex is an in-plane circulation of magnetization around a nanometer-scale central core with out-of-plane magnetization pointing either up or down. Circulation of the magnetization, known as vortex chirality (VC), also has two possible states depending on the sense of circulation: clockwise (CW) and counterclockwise (CCW). Its potential for storing two units of information in a single cell lies in the fact that the polarities of the core and the VC states can be controlled independently [1]. However efficient and reliable switching of the core and chirality pose significant technological challenges.