Antiferromagnetic spinmechatronics

About the project

Most people are familiar with the idea that electrons have properties such as charge and mass, but electrons also have a third property, namely, spin. The spin property of the electrons was first demonstrated in the famous Stern-Gerlach experiment of 1922, in which a beam of particles was sent through an inhomogeneous magnetic field, and different deflections of particles with opposite spins were observed. Unlike charge and mass, which are scalar quantities, spin is a vector quantity, and there is also a magnetic moment associated with each spin. Thus, each electron carries a small magnetic moment, and in ferromagnets, these moments are polarized in the same direction when the system is in equilibrium. In antiferromagnets, however, the spins are ordered in a regular pattern with neighboring spins pointing in opposite directions, such that the net magnetization is zero at equilibrium.  

Spinmechatronics is a technology that exploits the spin property of the electron to produce nanoscale mechanical devices, e.g., ultra-small engines and charge pumps that are driven by the collective spin excitations (the spin waves) of magnetic materials. So far, this technology has mainly concentrated on implementing ferromagnetic elements in spinmechatronic devices. The ultimate goal of this research project is to open a significant new area of research, which concentrates on the usage of antiferromagnets in spinmechatronics. Characteristic properties of the antiferromagnets, which make them particularly attractive for use in spinmechatronics, are their ultrafast spin dynamics and high stability with respect to magnetic fields. The anticipated application potential of our findings is in developing new ultra-fast nanoscale spinmechatronic devices with improved stability and novel forms of output signals.