Andrea CAVALLERI
I will discuss how intense and coherent electromagnetic radiation at Tera-Hertz and mid-infrared frequencies can be used to drive complex solids. Collective excitations are driven nonlinearly, leading to coupling amongst otherwise virtually non-interacting normal modes of the material. Driving gives rise to non-thermal states with unconventional properties, and sometimes with emergent order. Interesting examples involve the nonlinear control of the crystal lattice, used to induce magnetic order, ferroelectricity and non-equilibrium superconductivity at high temperatures.