"Nonlinear phononics: Coherent control of functional solids"
This event is part of the Physics Department Colloquia Series.
In this lecture, I will discuss how coherent electromagnetic radiation at infrared and TeraHertz frequencies can be used to drive atoms within the crystal lattice of a solid. For strong enough fields, the response of the lattice is nonlinear, and energy flows between different normal modes of the solid.
I will discuss how phononics can be used to manipulate ferroelectricity, magnetism and superconductivity, and will reflect on the underlying mechanisms, which are understood for some but not all these phenomena. Throughout the lecture, I will also discuss how femtosecond x-ray beams from free electron lasers allow for the reconstruction of atomic structure during these non-equilibrium processes.
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