Optical Control in High Tc Superconductors
In this talk, I will discuss some our recent work aimed at controlling the properties of high Tc cuprates with light. We use coherent THz radiation to drive excitations like phonons nonlinearly, and manipulate emergent properties. I will cover our recent work on the light enhancement of coherence in the bilayer 214 single layer cuprates and in bilayer cuprates like YBa2Cu3O6+x. We observe strengthening of superconductivity below Tc and possible transient superconductivity above Tc. I will discuss the combination of THz control also with Ultrafast X-ray probing, as achieved at Free Electron Lasers.