6 papers
Optimized near-field optical response via adaptive tip illumination
Tao Chen, Wei Wang, Ziyang Gan +7
The performance of tip-enhanced optical microscopy is often limited by inefficient coupling of the excitation field to the plasmonic tip apex, as well as by thermal drift and optic…
Self-consistent evaluation of the Berry connection for Wannier functions
Martin Thümmler, Thomas Lettau, Alexander Croy +2
The Berry connection is a gauge-dependent quantity frequently used to describe the optical response of solids. Its evaluation requires a k-derivative with respect to the cell perio…
Modeling high-order harmonic generation in quantum dots using a real-space tight-binding approach
Martin Thümmler, Alexander Croy, Ulf Peschel +1
Recently, the size-dependence of high-order harmonic generation (HHG) in quantum dots has been investigated experimentally. In particular, for longer driving wavelengths and QDs sm…
Semiconductor Bloch equations in Wannier gauge with well-behaved dephasing
Martin Thümmler, Thomas Lettau, Alexander Croy +2
The semiconductor Bloch equations (SBEs) with a dephasing operator for the microscopic polarizations are a well established approach to simulate high-harmonic spectra in solids. We…
Ultrafast Coherent Bandgap Modulation Probed by Parametric Nonlinear Optics
Sebastian Klimmer, Thomas Lettau, Laura Valencia Molina +5
Light-matter interactions in crystals are powerful tools that seamlessly allow both functionalities of sizeable bandgap modulation and non-invasive spectroscopy. While we often ass…
Real-time simulations of laser-induced electron excitations in crystalline ZnO
Xiao Chen, Thomas Lettau, Ulf Peschel +2
We investigate non-equilibrium electron dynamics in crystalline ZnO induced by ultrashort, relatively intense, infrared laser pulses. Our focus is on understanding the mechanism th…