A5044190697- Photonic Crystals and Applications
- Photonic and Optical Devices
- Plasmonic and Surface Plasmon Research
- Optical Coatings and Gratings
- Mechanical and Optical Resonators
- Quantum Information and Cryptography
- Random lasers and scattering media
- Advanced Fiber Laser Technologies
- Electromagnetic Simulation and Numerical Methods
- Quantum optics and atomic interactions
- Nonlinear Photonic Systems
- Metamaterials and Metasurfaces Applications
- Quantum Electrodynamics and Casimir Effect
- Fern and Epiphyte Biology
- Neural Networks and Reservoir Computing
- Gold and Silver Nanoparticles Synthesis and Applications
- Cold Atom Physics and Bose-Einstein Condensates
- Quantum Mechanics and Applications
- Advanced Thermodynamics and Statistical Mechanics
- Silicon Nanostructures and Photoluminescence
- Semiconductor Lasers and Optical Devices
- Quantum Mechanics and Non-Hermitian Physics
- Spectroscopy and Quantum Chemical Studies
- Topological Materials and Phenomena
- Thermal Radiation and Cooling Technologies
Max-Born-Institute for Nonlinear Optics and Short Pulse Spectroscopy
2015-2024
Humboldt-Universität zu Berlin
2015-2024
Humboldt State University
2022
Forschungsverbund Berlin
2019-2021
Karlsruhe Institute of Technology
2006-2020
Weatherford College
2020
Institut für angewandte Photonik
2017
Friedrich-Alexander-Universität Erlangen-Nürnberg
2011
Karlsruhe University of Education
2003-2009
Bielefeld University
2009
We present a detailed study of photonic band structure in certain self-organizing systems that self-assemble into large-scale crystals with gaps (PBGs) or pseudogaps the near-visible frequency regime. These include colloidal suspensions, inverted opals, and macroporous silicon. show complete three-dimensional PBGs spanning roughly 10% 15% gap center are attainable by incomplete infiltration an opal silicon germanium, respectively. The both face cubic hexagonal close packed evaluated....
We demonstrate that when an optically birefringent nematic liquid crystal is infiltrated into the void regions of inverse opal, photonic-band-gap (PBG) material, resulting composite material exhibits a completely tunable PBG. In particular, three-dimensional PBG can be opened or closed by applying electric field which rotates axis molecules relative to opal backbone. Tunable light localization effects may realized controlling orientational disorder in nematic.
Abstract Recent progress in direct laser writing of three‐dimensional (3D) polymer nanostructures for photonics is reviewed. This technology has reached a level maturity at which it can be considered as the 3D analogue planar electron‐beam lithography. Combined with atomic‐layer deposition and/or chemical‐vapor dielectrics—the analogues evaporation technologies, templates converted or inverted into high‐refractive‐index‐contrast nanostructures. Examples discussed this review include positive...
We introduce a second quantization scheme based on quasinormal modes, which are the dissipative modes of leaky optical cavities and plasmonic resonators with complex eigenfrequencies. The theory enables construction multi-plasmon/photon Fock states for arbitrary three-dimensional gives solid understanding to limits phenomenological Jaynes-Cummings models. In general case, we show how different interfere through an off-diagonal mode coupling demonstrate these results affect cavity-modified...
The photonic band gap of a two-dimensional crystal is continuously tuned using the temperature dependent refractive index liquid crystal. Liquid $E7$ was infiltrated into air pores macroporous silicon with triangular lattice pitch 1.58 $\ensuremath{\mu}$m and wavelength range 3.3--5.7 \ensuremath{\mu}m. After infiltration, for H polarized field shifted dramatically to 4.4--6.0 \ensuremath{\mu}m while that E-polarized collapsed. As sample heated nematic-isotropic phase transition...
Photonic crystals can be thought of as optical analogues semiconductors. Here recent advances in photonic based on silicon are reviewed. After summarizing the theory bandgap materials, preparation and linear properties 1D, 2D, 3D silicon-based discussed. Laterally structured porous with a defect line is shown Figure.
We have fabricated a two-dimensional photonic band structure based on macroporous silicon with gap common to both polarizations and centered at 5 μm. A triangular lattice of circular air rods constant 2.3 μm was etched 75 deep in an n-type substrate by electrochemical pore formation hydrofluoric acid. The porous layer then micromechanically structured such way that 200 thick free-standing bars material were left over the substrate. These used for measuring transmission lattice. results...
We fabricate three-dimensional photoresist templates by means of laser holography. In particular, fcc structures are achieved placing a specially designed “prism” onto the surface. This solves problem previous work, in which refraction at air–photoresist interface made it impossible to obtain required angles light wave vectors inside photoresist. The characterized scanning electron microscopy as well optical transmission spectroscopy, agree with numerical band-structure calculations.
We present a detailed analysis of the dynamics photon transport in waveguiding systems presence two-level system. In these systems, quantum interference effects generate strong effective optical nonlinearity on few-photon level. clarify relevant physical mechanisms through an appropriate many-body approach. Based this, we demonstrate that single-particle photon-atom bound state with energy outside band can be excited via multi-particle scattering processes. further show trapping are robust...
We present a formalism for the description of fluorescence from optically active materials embedded in photonic crystal structure possessing band gap or pseudogap. An electromagnetic field expansion terms Bloch modes is used to develop equations local density photon available emitting atoms either high low dielectric regions crystal. then obtain expressions spectra and emission dynamics luminescent crystals. The validity our demonstrated through calculation relevant quantities model...
Abstract This article reviews the state of recently developed discontinuous Galerkin finite element method for efficient numerical treatment nanophotonic systems. approach combines accurate and flexible spatial discretisation classical elements with time stepping capabilities. We describe in detail underlying principles technique its application to simulation complex structures. In addition, formulations both time‐ frequency‐domain solvers are provided specific advantages limitations...
We present a biorthogonal approach for modeling the response of localized electromagnetic resonators using quasinormal modes, which represent natural, dissipative eigenmodes system with complex frequencies. For many problems interest in optics and nanophotonics, modes constitute powerful tool, provides coherent, precise, accessible derivation associated theory, enabling an illustrative connection between different approaches that exist literature.
Abstract Compact, on‐chip spectrometers exploiting tailored disorder for broadband light scattering enable high‐resolution signal analysis while maintaining a small device footprint. Due to multiple events of in the disordered medium, effective path length is significantly enhanced. Here, are realized visible and near‐infrared wavelengths by combining an efficient fiber‐to‐chip coupling approach with area transparent silicon nitride waveguiding structure. Air holes etched into structured...
Rooted in quantum optics and benefiting from its well-established foundations, strong coupling nanophotonics has experienced increasing popularity recent years. With being an experiment-driven field, the absence of appropriate theoretical methods to describe ground-breaking advances often emerged as important issue. To address this problem, temptation directly transfer extend concepts already available is strong, even if a rigorous justification not always available. In review we discuss...
We report on the fabrication and optical characterization of a three-dimensional (3D) photonic crystal basis macroporous silicon. The structure consists 2D array air pores in silicon whose diameter is varied (modulated) periodically with depth. bandstructure resulting 3D hexagonal calculated compared transmission measurements. described allows to adjust dispersion relation along pore axis almost independently from plane perpendicular axis.
We study second-harmonic generation from gold split-ring resonators on a crystalline GaAs substrate. By systematically varying the relative orientation of with respect to incident linear polarization light and crystallographic axes, we unambiguously identify nonlinear contribution that originates specifically interplay local fields bulk second-order nonlinear-susceptibility tensor. The experimental results are in good agreement theoretical modeling.
We analyze the role of quantum interference effects induced by an embedded two-level system on photon transport properties in waveguiding structures that exhibit cutoffs (band edges) their dispersion relation. In particular, we demonstrate these systems invariably single-particle photon-atom bound states and strong effective nonlinear responses few-photon level. Based this, find may be tuned via underlying relation occupation can controlled multiparticle scattering processes. This opens...
Since the very first proposition of photonic crystals, their influence on dynamics spontaneous emission has been great interest. The radiation is described by an integration kernel which--in a spectral representation--comprises two equally important contributions: Lamb shift and radiative contribution to linewidth. latter connected density states via Fermi's golden rule. To our knowledge, we present spatially resolved measurement complete in crystal its local over wide range. this end study...
Their intrinsic properties render single quantum systems as ideal tools for enhanced sensing and microscopy. As an additional benefit, their size is typically on atomic scale that enables with very high spatial resolution. Here, we report utilizing a nitrogen vacancy center in nanodiamond performing three-dimensional scanning-probe fluorescence lifetime imaging By measuring changes of the emitter's lifetime, information local density optical states acquired at nanoscale. Three-dimensional ab...