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TT: Fachverband Tiefe Temperaturen
TT 44: Focus Session: Frontiers of Electronic Structure Theory - Non-Equilibrium Phenomena at the Nano-Scale III (organized by O)
TT 44.4: Vortrag
Dienstag, 1. April 2014, 11:30–11:45, TRE Ma
Nonlinear optics by means of the dynamical Berry phase: Application to second- and third-harmonic generation — •Claudio Attaccalite1 and Myrta Gruning2 — 1Univ. Grenoble Alpes/CNRS, Institut Neel, F-38042 Grenoble, France — 2School of Mathematics and Physics, Queen's University Belfast, Belfast BT7 1NN, Northern Ireland, UK
We present an real-time approach to study nonlinear optical properties in Condensed Matter systems that is especially suitable for crystalline solids. The equation of motions and the coupling of the electrons with the external electric field are derived from the Berry phase formulation of the dynamical polarization. Many-body effects are introduced by adding single-particle operators to the independent-particle Hamiltonian. Specifically we include crystal local field effects, renormalization of the energy levels and excitonic effects. The approach is validated by calculating the second and third harmonic generation of bulk semiconductors. Finally we present second-harmonic generation spectrum of h-BN or MoS2 monolayers and show that correlation effects double the signal intensity at the excitonic resonances with respect to the contribution from independent electronic transitions.
References: [1] Nonlinear optics from ab-initio by means of the dynamical Berry-phase http://arxiv.org/abs/1309.4012 [2] Second Harmonic Generation in h-BN and MoS2 monolayers: the role of electron-hole interaction http://arxiv.org/abs/1310.7459