Nicolas Tancogne-Dejean I Advances in optical spectroscopies of solids: Insight from ab initio simulations

Nicolas Tancogne-Dejean de MPSD , Hambourg

All-optical spectroscopy of matter is a well-established technique to access properties of electrons and quasi-particles in matter. The description of these optical properties is usually done employing ab initio methods based on linear response theory.

The recent advances in experimental techniques have opened up the possibility to develop novel types of spectroscopies based ultrashort and intense laser pulses, allowing for instance to access non-equilibrium dynamics of electronic systems or to allow for exploring non-equilibrium phase diagram of correlated materials. In particular, the strong-field electronic dynamics in solids has received a lot of attention, in particular due to the experimental observation of high-harmonic generation in solids. The dynamics associated with strong fields implies the manipulation of the electrons on the attosecond time-scale, which could lead to tremendous applications in the emerging fields of strong-field optoelectronics and petahertz electronics, as well as the spectroscopy of phenomena occurring on the attosecond to femtosecond timescale.

In this talk, I will show that ab initio calculations, performed within the framework of real-time time-dependent density functional theory (TDDFT), can help unraveling the microscopic mechanisms responsible for ultrafast electron dynamics in solids and low-dimensional materials. The predictive power of this approach is demonstrated by directly comparing the simulations results to the experimental data. Interesting phenomena are also predicted to occur when a strong laser interacts with different type of bulk materials, including correlated magnetic materials.