Junyi Wu, Myoung-Woo Yoo, and David G. Cahill
NSF MRSEC Grant no. DMR-1720633
In collaboration with Daniel Shoemaker (MatSE), Andre Schleife (MatSE), Gina Lorenz (Physics), Nadya Mason (Physics), Matthew Gilbert (ECE), and Axel Hoffmann (MatSE) we are working to advance fundamental understanding of the synthesis-structure-property relationships of metallic anti-ferromagnetic materials. Our goal is to answer open questions concerning the coupling of magnetic order, optical fields, electronic excitations, and lattice vibrations that underlie fundamental limits on the control of magnetization dynamics using ultrafast optics, ultrafast temperature excursions, and ultrafast currents of heat and charge. Specifically, we seek fundamental understanding, from close collaboration between theory and experiment, of limits to:
- The rate at which the AFM order parameter can be manipulated by a fast temperature excursion.
- The current-induced internal magnetic field that can be generated by the interplay of spin-orbit coupling and site symmetry of magnetic ions of an AFM crystal.
- The generation of spin currents, spin accumulation, and spin-orbit torques within the bulk of metallic AFM by charge currents and the spin Hall effect.
- The extent to which spin-orbit torques can be enhanced at interfaces between metallic AFMs and non-magnetic or ferromagnetic metals.
- The switching of the AFM order parameter between degenerate orientations.
- The strength of magneto-optic effects in metallic AFMs including interactions with the angular momentum of light, via inverse Faraday and optical-spin-transfer torque, and the potential of these driving forces for optical control of the AFM order parameter.