@inproceedings{BurgerSchmidtZschiedrich2003, author = {Burger, Sven and Schmidt, Frank and Zschiedrich, Lin}, title = {A fast and efficient Finite-Element Solver for 2D and 3D Photonic Band-Gap Problems}, booktitle = {Dig. LEOS/IEEE 2003 Summer Topicals}, doi = {10.1109/LEOSST.2003.1224282}, pages = {75}, year = {2003}, language = {en} } @inproceedings{BurgerZschiedrichSchmidt2010, author = {Burger, Sven and Zschiedrich, Lin and Schmidt, Frank}, title = {3D FEM Simulations of High-Q Resonances in Photonic Crystal Microcavities}, booktitle = {Integrated Photonics Research, Silicon and Nanophotonics}, publisher = {OSA}, doi = {10.1364/IPRSN.2010.IWB7}, pages = {IWB7}, year = {2010}, language = {en} } @inproceedings{BurgerSchmidtZschiedrich2010, author = {Burger, Sven and Schmidt, Frank and Zschiedrich, Lin}, title = {FEM simulation of resonances in low-Q cavities for plasmon lasers}, booktitle = {International Workshop on Photonic Nanomaterials}, editor = {Jena, Friedrich-Schiller-Universit{\"a}t}, isbn = {978-3-00-031358-5}, pages = {36}, year = {2010}, language = {en} } @inproceedings{BurgerSchmidtZschiedrich2010, author = {Burger, Sven and Schmidt, Frank and Zschiedrich, Lin}, title = {Numerical investigation of optical resonances in circular grating resonators}, volume = {7606}, booktitle = {Silicon Photonics V}, publisher = {Proc. SPIE}, doi = {10.1117/12.842061}, pages = {760610}, year = {2010}, language = {en} } @inproceedings{BurgerSchmidtZschiedrich2010, author = {Burger, Sven and Schmidt, Frank and Zschiedrich, Lin}, title = {Numerical Investigation of Photonic Crystal Microcavities in Silicon-on-Insulator Waveguides}, volume = {7609}, booktitle = {Photonic and Phononic Crystal Materials and Devices X}, publisher = {Proc. SPIE}, doi = {10.1117/12.841867}, pages = {76091Q}, year = {2010}, language = {en} } @inproceedings{PomplunZschiedrichBurgeretal.2010, author = {Pomplun, Jan and Zschiedrich, Lin and Burger, Sven and Schmidt, Frank and Tyminski, Jacek and Flagello, Donis and Toshiharu, N.}, title = {Reduced basis method for source mask optimization}, volume = {7823}, booktitle = {Photomask Technology}, publisher = {Proc. SPIE}, doi = {10.1117/12.866101}, pages = {78230E}, year = {2010}, language = {en} } @inproceedings{BurgerSchaedleZschiedrichetal.2006, author = {Burger, Sven and Sch{\"a}dle, Achim and Zschiedrich, Lin and Schmidt, Frank}, title = {Advanced FEM Analysis of Nano-Optical Devices}, volume = {6195}, booktitle = {Nanophotonics}, editor = {Andrews, David L. and Nunzi, Jean-Michel and Ostendorf, Andreas}, publisher = {Proc. SPIE}, doi = {10.1117/12.662942}, pages = {72 -- 82}, year = {2006}, language = {en} } @inproceedings{BurgerKloseMaerzetal.2004, author = {Burger, Sven and Klose, Roland and M{\"a}rz, Reinhard and Sch{\"a}dle, Achim and Schmidt, Frank and Zschiedrich, Lin}, title = {Efficient Finite Element Methods for the Design of Microoptical Components}, booktitle = {Proc. Microoptics Conf. 2004}, year = {2004}, language = {en} } @inproceedings{BurgerKloseSchaedleetal.2005, author = {Burger, Sven and Klose, Roland and Sch{\"a}dle, Achim and Schmidt, Frank and Zschiedrich, Lin}, title = {FEM modelling of 3D photonic crystals and photonic crystal waveguides}, volume = {5728}, booktitle = {Integrated Optics : Devices, Materials and Technologies IX}, editor = {Sidorin, Y. and W{\"a}chter, Christoph}, publisher = {Proc. SPIE}, doi = {10.1117/12.585895}, pages = {164 -- 173}, year = {2005}, language = {en} } @incollection{BurgerKloseSchaedleetal.2006, author = {Burger, Sven and Klose, Roland and Sch{\"a}dle, Achim and Schmidt, Frank and Zschiedrich, Lin}, title = {Adaptive FEM solver for the computation of electromagnetic eigenmodes in 3D photonic crystal structures}, booktitle = {Scientific Computing in Electrical Engineering}, publisher = {Springer Verlag}, doi = {10.1007/978-3-540-32862-9_24}, pages = {169 -- 175}, year = {2006}, language = {en} } @inproceedings{BurgerKleemannZschiedrichetal.2009, author = {Burger, Sven and Kleemann, B. and Zschiedrich, Lin and Schmidt, Frank}, title = {Finite-Element Simulations of Light Propagation through Circular Subwavelength Apertures}, volume = {7366}, booktitle = {Microtechnologies for the New Millenium}, publisher = {Proc. SPIE}, doi = {10.1117/12.822828}, pages = {736621}, year = {2009}, language = {en} } @inproceedings{BurgerKoehleZschiedrichetal.2006, author = {Burger, Sven and K{\"o}hle, Roderick and Zschiedrich, Lin and Nguyen, H. and Schmidt, Frank and M{\"a}rz, Reinhard and N{\"o}lscher, Christoph}, title = {Rigorous Simulation of 3D Masks}, volume = {6349}, booktitle = {Photomask Technology}, editor = {Martin, P. and Naber, R.}, publisher = {Proc. SPIE}, pages = {63494Z}, year = {2006}, language = {en} } @inproceedings{DeuflhardFrieseSchmidtetal.1996, author = {Deuflhard, Peter and Friese, T. and Schmidt, Frank and M{\"a}rz, Reinhard and Nolting, Hans-Peter}, title = {Effiziente Eigenmodenberechnung f{\"u}r den Entwurf integriert-optischer Chips}, booktitle = {Mathematik - Schl{\"u}sseltechnologie f{\"u}r die Zukunft}, editor = {et al. Hoffmann, K.-H.}, publisher = {Springer Verlag}, pages = {267 -- 279}, year = {1996}, language = {en} } @misc{GutscheJuddSchmidt2014, author = {Gutsche, Philipp and Judd, Thomas and Schmidt, Frank}, title = {A convergence study of different Rigorous Coupled Wave Analysis (RCWA) approaches to time-harmonic electromagnetic scattering problems with applications to nanooptical structures}, journal = {Verhandlungen der Deutschen Physikalischen Gesellschaft (DPG-Fr{\"u}hjahrstagung Berlin 2014)}, year = {2014}, abstract = {Reliable numerical simulations of nano-optical structures are the key for design and pre-fabrication processes in diverse disciplines such as lithography in semiconductor industries, spectroscopy of biological molecules, optimization of quantum dot cavities for single-photon sources, and computation of atomic forces like the Casimir Effect. For these purposes a variety of different methods, e.g. FDTD, FEM and RCWA, are in use. On the one hand, FDTD and FEM are investigated intensively - both in mathematics and numerical experiments - and their approximations and convergence properties are well known. On the other hand, there is a lack of these insights in RCWA. In spite of this, RCWA is commonly used to simulate a wide range of systems. We review historical and modern contributions to convergence improvements with respect to RCWA from the early sugesstions to modern developments. We study the convergence rates of the open-source software S4 and analyze the algorithmic properties in detail. Furthermore, we compare RCWA and FEM simulations for different classes of problems including 1D-binary gratings and 2D-periodic photonic crystals.}, language = {en} } @inproceedings{BurgerGutscheHammerschmidtetal.2015, author = {Burger, Sven and Gutsche, Philipp and Hammerschmidt, Martin and Herrmann, Sven and Pomplun, Jan and Schmidt, Frank and Wohlfeil, Benjamin and Zschiedrich, Lin}, title = {Hp-finite-elements for simulating electromagnetic fields in optical devices with rough textures}, volume = {9630}, booktitle = {Proc. SPIE}, arxiv = {http://arxiv.org/abs/1510.02607}, doi = {10.1117/12.2190119}, pages = {96300S}, year = {2015}, language = {en} } @misc{HammerschmidtHerrmannPomplunetal.2015, author = {Hammerschmidt, Martin and Herrmann, Sven and Pomplun, Jan and Zschiedrich, Lin and Burger, Sven and Schmidt, Frank}, title = {Reduced basis method for Maxwell's equations with resonance phenomena}, volume = {9630}, journal = {Proc. SPIE}, issn = {1438-0064}, doi = {10.1117/12.2190425}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-55687}, pages = {96300R}, year = {2015}, abstract = {Rigorous optical simulations of 3-dimensional nano-photonic structures are an important tool in the analysis and optimization of scattering properties of nano-photonic devices or parameter reconstruction. To construct geometrically accurate models of complex structured nano-photonic devices the finite element method (FEM) is ideally suited due to its flexibility in the geometrical modeling and superior convergence properties. Reduced order models such as the reduced basis method (RBM) allow to construct self-adaptive, error-controlled, very low dimensional approximations for input-output relationships which can be evaluated orders of magnitude faster than the full model. This is advantageous in applications requiring the solution of Maxwell's equations for multiple parameters or a single parameter but in real time. We present a reduced basis method for 3D Maxwell's equations based on the finite element method which allows variations of geometric as well as material and frequency parameters. We demonstrate accuracy and efficiency of the method for a light scattering problem exhibiting a resonance in the electric field.}, language = {en} } @inproceedings{BurgerZschiedrichPomplunetal.2015, author = {Burger, Sven and Zschiedrich, Lin and Pomplun, Jan and Herrmann, Sven and Schmidt, Frank}, title = {hp-finite element method for simulating light scattering from complex 3D structures}, volume = {9424}, booktitle = {Proc. SPIE}, arxiv = {http://arxiv.org/abs/1503.06617}, doi = {10.1117/12.2085795}, pages = {94240Z}, year = {2015}, language = {en} } @article{ShchukinLedentsovJrKroppetal.2014, author = {Shchukin, Vitaly and Ledentsov, Jr., Nikolay and Kropp, J{\"o}rg-R. and Steinle, Gunther and Ledentsov, Jr., Nikolay and Burger, Sven and Schmidt, Frank}, title = {Single-Mode Vertical Cavity Surface Emitting Laser via Oxide-Aperture-Engineering of Leakage of High Order Transverse Modes}, volume = {50}, journal = {IEEE J. Quant. Electron.}, number = {12}, doi = {10.1109/JQE.2014.2364544}, pages = {990 -- 995}, year = {2014}, language = {en} } @book{LavrinenkoLaegsgaardGregersenetal.2014, author = {Lavrinenko, Andrei and Laegsgaard, Jesper and Gregersen, Niels and Schmidt, Frank and Soendergaard, Thomas}, title = {Numerical Methods in Photonics}, editor = {Wyant, James C.}, publisher = {CRC Press}, isbn = {9781466563889}, year = {2014}, language = {en} } @inproceedings{LedentsovJrKroppShchukinetal.2015, author = {Ledentsov, Jr., Nikolay and Kropp, J{\"o}rg-R. and Shchukin, Vitaly and Steinle, Gunther and Ledentsov, Jr., Nikolay and Turkiewicz, Jarek P. and Wu, Bo and Shaofeng, Qiu and Ma, Yanan and Zhiyong, Feng and Burger, Sven and Schmidt, Frank and Caspar, Christoph and Freund, Ronald and Choquette, Kent D.}, title = {High-speed modulation, wavelength, and mode control in vertical-cavity surface-emitting lasers}, volume = {9381}, booktitle = {Proc. SPIE}, doi = {10.1117/12.2082951}, pages = {93810F}, year = {2015}, language = {en} } @inproceedings{ShchukinLedentsovJrKroppetal.2015, author = {Shchukin, Vitaly and Ledentsov, Jr., Nikolay and Kropp, J{\"o}rg-R. and Steinle, Gunther and Ledentsov, Jr., Nikolay and Choquette, Kent D. and Burger, Sven and Schmidt, Frank}, title = {Engineering of optical modes in vertical-cavity microresonators by aperture placement: applications to single-mode and near-field lasers}, volume = {9381}, booktitle = {Proc. SPIE}, doi = {10.1117/12.2077012}, pages = {93810V}, year = {2015}, language = {en} } @incollection{LedentsovJrShchukinLedentsovJretal.2016, author = {Ledentsov, Jr., Nikolay and Shchukin, Vitaly and Ledentsov, Jr., Nikolay and Kropp, J{\"o}rg-R. and Burger, Sven and Schmidt, Frank}, title = {New Generation of Vertical-Cavity Surface-Emitting Lasers for Optical Interconnects}, booktitle = {Future Trends in Microelectronics: Journey into the Unknown}, publisher = {John Wiley \& Sons}, doi = {10.1002/9781119069225.ch3-5}, year = {2016}, language = {en} } @inproceedings{LockauHammerschmidtHaschkeetal.2014, author = {Lockau, Daniel and Hammerschmidt, Martin and Haschke, Jan and Blome, Mark and Ruske, Florian and Schmidt, Frank and Rech, Bernd}, title = {A comparison of scattering and non-scattering anti-reflection designs for back contacted polycrystalline thin film silicon solar cells in superstrate configuration}, volume = {9140}, booktitle = {Proc. SPIE}, doi = {10.1117/12.2052362}, pages = {914006}, year = {2014}, language = {en} } @inproceedings{ManleySchmidtSchmid2013, author = {Manley, Phillip and Schmidt, Frank and Schmid, Martina}, title = {Light extraction from plasmonic particles with dielectric shells and overcoatings}, booktitle = {Renewable Energy and the Environment}, publisher = {Optical Society of America}, doi = {10.1364/PV.2013.PW3B.7}, pages = {PW3B.7}, year = {2013}, language = {en} } @article{RuprechtSchaedleSchmidt2013, author = {Ruprecht, Daniel and Sch{\"a}dle, Achim and Schmidt, Frank}, title = {Transparent boundary conditions based on the pole condition for time-dependent, two-dimensional problems}, volume = {29}, journal = {Numerical Methods for Partial Differential Equations}, number = {4}, doi = {10.1002/num.21759}, pages = {1367 -- 1390}, year = {2013}, language = {en} } @misc{HammerschmidtPomplunBurgeretal.2014, author = {Hammerschmidt, Martin and Pomplun, Jan and Burger, Sven and Schmidt, Frank}, title = {Adaptive sampling strategies for efficient parameter scans in nano-photonic device simulations}, issn = {1438-0064}, doi = {10.1117/12.2036363}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-50395}, year = {2014}, abstract = {Rigorous optical simulations are an important tool in optimizing scattering properties of nano-photonic devices and are used, for example, in solar cell optimization. The finite element method (FEM) yields rigorous, time-harmonic, high accuracy solutions of the full 3D vectorial Maxwell's equations [1] and furthermore allows for great flexibility and accuracy in the geometrical modeling of these often complex shaped 3D nano-structures. A major drawback of frequency domain methods is the limitation of single frequency evaluations. For example the accurate computation of the short circuit current density of an amorphous silicon / micro-crystalline multi-junction thin film solar cell may require the solution of Maxwell's equations for over a hundred different wavelengths if an equidistant sampling strategy is employed. Also in optical metrology, wavelength scans are frequently used to reconstruct unknown geometrical and material properties of optical systems numerically from measured scatterometric data. In our contribution we present several adaptive numerical integration and sampling routines and study their efficiency in the context of the determination of generation rate profiles of solar cells. We show that these strategies lead to a reduction in the computational effort without loss of accuracy. We discuss the employment of tangential information in a Hermite interpolation scheme to achieve similar accuracy on coarser grids. We explore the usability of these strategies for scatterometry and solar cell simulations.}, language = {en} } @misc{HammerschmidtLockauZschiedrichetal.2014, author = {Hammerschmidt, Martin and Lockau, Daniel and Zschiedrich, Lin and Schmidt, Frank}, title = {Optical modelling of incoherent substrate light-trapping in silicon thin film multi-junction solar cells with finite elements and domain decomposition}, issn = {1438-0064}, doi = {10.1117/12.2036346}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-50410}, year = {2014}, abstract = {In many experimentally realized applications, e.g. photonic crystals, solar cells and light-emitting diodes, nano-photonic systems are coupled to a thick substrate layer, which in certain cases has to be included as a part of the optical system. The finite element method (FEM) yields rigorous, high accuracy solutions of full 3D vectorial Maxwell's equations [1] and allows for great flexibility and accuracy in the geometrical modelling. Time-harmonic FEM solvers have been combined with Fourier methods in domain decomposition algorithms to compute coherent solutions of these coupled system. [2,3] The basic idea of a domain decomposition approach lies in a decomposition of the domain into smaller subdomains, separate calculations of the solutions and coupling of these solutions on adjacent subdomains. In experiments light sources are often not perfectly monochromatic and hence a comparision to simulation results might only be justified if the simulation results, which include interference patterns in the substrate, are spectrally averaged. In this contribution we present a scattering matrix domain decomposition algorithm for Maxwell's equations based on FEM. We study its convergence and advantages in the context of optical simulations of silicon thin film multi-junction solar cells. This allows for substrate light-trapping to be included in optical simulations and leads to a more realistic estimation of light path enhancement factors in thin-film devices near the band edge.}, language = {en} } @misc{LockauHammerschmidtBlomeetal.2014, author = {Lockau, Daniel and Hammerschmidt, Martin and Blome, Mark and Schmidt, Frank}, title = {Optics of thin film solar cells}, volume = {1}, journal = {MATHEON-Mathematics for Key Technologies}, editor = {Deuflhard, Peter and et al.,}, publisher = {European Mathematical Society}, doi = {10.4171/137}, pages = {278 -- 279}, year = {2014}, language = {en} } @misc{HammerschmidtHerrmannBurgeretal.2016, author = {Hammerschmidt, Martin and Herrmann, Sven and Burger, Sven and Pomplun, Jan and Schmidt, Frank}, title = {Reduced basis method for the optimization of nano-photonic devices}, issn = {1438-0064}, doi = {10.1007/s11082-016-0530-1}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-57556}, year = {2016}, abstract = {Optical 3D simulations in many-query and real-time contexts require new solution strategies. We study an adaptive, error controlled reduced basis method for solving parametrized time-harmonic optical scattering problems. Application fields are, among others, design and optimization problems of nano-optical devices as well as inverse problems for parameter reconstructions occuring e. g. in optical metrology. The reduced basis method presented here relies on a finite element modeling of the scattering problem with parametrization of materials, geometries and sources.}, language = {en} } @misc{HammerschmidtHerrmannPomplunetal.2016, author = {Hammerschmidt, Martin and Herrmann, Sven and Pomplun, Jan and Burger, Sven and Schmidt, Frank}, title = {Model order reduction for the time-harmonic Maxwell equation applied to complex nanostructures}, volume = {9742}, journal = {Proc. SPIE}, issn = {1438-0064}, doi = {10.1117/12.2212367}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-57239}, pages = {97420M}, year = {2016}, abstract = {Fields such as optical metrology and computational lithography require fast and efficient methods for solving the time-harmonic Maxwell's equation. Highly accurate geometrical modeling and numerical accuracy atcomputational costs are a prerequisite for any simulation study of complex nano-structured photonic devices. We present a reduced basis method (RBM) for the time-harmonic electromagnetic scattering problem based on the hp-adaptive finite element solver JCMsuite capable of handling geometric and non-geometric parameter dependencies allowing for online evaluations in milliseconds. We apply the RBM to compute light-scatteringoptical wavelengths off periodic arrays of fin field-effect transistors (FinFETs) where geometrical properties such as the width and height of the fin and gate can vary in a large range.}, language = {en} } @misc{HammerschmidtBarthPomplunetal.2016, author = {Hammerschmidt, Martin and Barth, Carlo and Pomplun, Jan and Burger, Sven and Becker, Christiane and Schmidt, Frank}, title = {Reconstruction of photonic crystal geometries using a reduced basis method for nonlinear outputs}, issn = {1438-0064}, doi = {10.1117/12.2212482}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-57249}, year = {2016}, abstract = {Maxwell solvers based on the hp-adaptive finite element method allow for accurate geometrical modeling and high numerical accuracy. These features are indispensable for the optimization of optical properties or reconstruction of parameters through inverse processes. High computational complexity prohibits the evaluation of the solution for many parameters. We present a reduced basis method (RBM) for the time-harmonic electromagnetic scattering problem allowing to compute solutions for a parameter configuration orders of magnitude faster. The RBM allows to evaluate linear and nonlinear outputs of interest like Fourier transform or the enhancement of the electromagnetic field in milliseconds. We apply the RBM to compute light-scattering off two dimensional photonic crystal structures made of silicon and reconstruct geometrical parameters.}, language = {en} } @misc{GutschePoulikakosBurgeretal.2016, author = {Gutsche, Philipp and Poulikakos, Lisa and Burger, Sven and Hammerschmidt, Martin and Schmidt, Frank}, title = {Optical chirality: conservation law in arbitrary space}, journal = {606. WE-Heraeus-Seminar on Nanophotonics and Complex Spatial Modes of Light}, year = {2016}, abstract = {The introduction of the near-field quantity of optical chirality has emerged in various numerical and few experimental studies of local chirality enhancement due to its relation to the excitation rate of chiral molecules. This time-even pseudoscalar has been dismissed as being a higher-order version of helicity. Nevertheless, we revisit the derivation of the underlying conservation law and define optical chirality in media similar to. We identify the mechanism of chirality conversion by either inhomogeneous or anisotropic space to complement the conservation of optical chirality. The conservation law of optical chirality in arbitrary space enables the extension of the concept of polarization to the near-field where no distiniguished propagation direction of light is present. We show that the connection of electromagnetic energy and optical chirality provide the ability to define a circular polarization basis in time-harmonic near-field analysis. In order to illustrate our theory, we present electromagnetic field simulations of simple as well as more complex nanostructures. Results using the well-known far-field polarization concept are readily reproduced and extended from the point of view of chirality conversion.}, language = {en} } @inproceedings{BurgerHammerschmidtHerrmannetal.2015, author = {Burger, Sven and Hammerschmidt, Martin and Herrmann, Sven and Pomplun, Jan and Schmidt, Frank}, title = {Reduced basis methods for optimization of nano-photonic devices}, booktitle = {Proc. Int. Conf. Numerical Simulation of Optoelectronic Devices (NUSOD)}, doi = {10.1109/NUSOD.2015.7292871}, pages = {159}, year = {2015}, language = {en} } @article{LedentsovJrShchukinLedentsovJretal.2016, author = {Ledentsov, Jr., Nikolay and Shchukin, Vitaly and Ledentsov, Jr., Nikolay and Kropp, J{\"o}rg-R. and Burger, Sven and Schmidt, Frank}, title = {Direct Evidence of the Leaky Emission in Oxide-Confined Vertical Cavity Lasers}, volume = {52}, journal = {IEEE J. Quant. Electron.}, number = {3}, doi = {10.1109/JQE.2016.2518081}, pages = {2400207}, year = {2016}, language = {en} } @inproceedings{JaegerBarthHammerschmidtetal.2015, author = {J{\"a}ger, Klaus and Barth, Carlo and Hammerschmidt, Martin and Herrmann, Sven and Burger, Sven and Schmidt, Frank and Becker, Christiane}, title = {Sinusoidal Nanotextures for Coupling Light into c-Si Thin-Film Solar Cells}, booktitle = {Light, Energy and the Environement 2015}, doi = {10.1364/PV.2015.PTu4B.3}, pages = {PTu4B.3}, year = {2015}, language = {en} } @inproceedings{BarthJaegerBurgeretal.2015, author = {Barth, Carlo and J{\"a}ger, Klaus and Burger, Sven and Hammerschmidt, Martin and Schmidt, Frank and Becker, Christiane}, title = {Design of Photonic Crystals with Near-Surface Field Enhancement}, booktitle = {Light, Energy and the Environement 2015}, doi = {10.1364/PV.2015.JTu5A.9}, pages = {JTu5A.9}, year = {2015}, language = {en} } @article{JaegerBarthHammerschmidtetal.2016, author = {J{\"a}ger, Klaus and Barth, Carlo and Hammerschmidt, Martin and Herrmann, Sven and Burger, Sven and Schmidt, Frank and Becker, Christiane}, title = {Simulations of sinusoidal nanotextures for coupling light into c-Si thin-film solar cells}, volume = {24}, journal = {Opt. Express}, doi = {10.1364/OE.24.00A569}, pages = {A569}, year = {2016}, language = {en} } @article{LedentsovJrShchukinKroppetal.2016, author = {Ledentsov, Jr., Nikolay and Shchukin, Vitaly and Kropp, J{\"o}rg-R. and Burger, Sven and Schmidt, Frank and Ledentsov, Jr., Nikolay}, title = {Direct visualization of the in-plane leakage of high-order transverse modes in vertical-cavity surface-emitting lasers mediated by oxide-aperture engineering}, volume = {9766}, journal = {Proc. SPIE}, doi = {10.1117/12.2208909}, pages = {976608}, year = {2016}, language = {en} } @article{PomplunBurgerZschiedrichetal.2016, author = {Pomplun, Jan and Burger, Sven and Zschiedrich, Lin and Gutsche, Philipp and Schmidt, Frank}, title = {Method for fast computation of angular light scattering spectra from 2D periodic arrays}, volume = {9778}, journal = {Proc. SPIE}, arxiv = {http://arxiv.org/abs/1603.04169}, doi = {10.1117/12.2219666}, pages = {977839}, year = {2016}, language = {en} } @article{GutschePoulikakosHammerschmidtetal.2016, author = {Gutsche, Philipp and Poulikakos, Lisa and Hammerschmidt, Martin and Burger, Sven and Schmidt, Frank}, title = {Time-harmonic optical chirality in inhomogeneous space}, volume = {9756}, journal = {Proc. SPIE}, arxiv = {http://arxiv.org/abs/1603.05011}, doi = {10.1117/12.2209551}, pages = {97560X}, year = {2016}, language = {en} } @article{HammerschmidtBarthPomplunetal.2016, author = {Hammerschmidt, Martin and Barth, Carlo and Pomplun, Jan and Burger, Sven and Becker, Christiane and Schmidt, Frank}, title = {Reconstruction of photonic crystal geometries using a reduced basis method for nonlinear outputs}, volume = {9756}, journal = {Proc. SPIE}, doi = {10.1117/12.2212482}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-58187}, pages = {97561R}, year = {2016}, abstract = {Maxwell solvers based on the hp-adaptive finite element method allow for accurate geometrical modeling and high numerical accuracy. These features are indispensable for the optimization of optical properties or reconstruction of parameters through inverse processes. High computational complexity prohibits the evaluation of the solution for many parameters. We present a reduced basis method (RBM) for the time-harmonic electromagnetic scattering problem allowing to compute solutions for a parameter configuration orders of magnitude faster. The RBM allows to evaluate linear and nonlinear outputs of interest like Fourier transform or the enhancement of the electromagnetic field in milliseconds. We apply the RBM to compute light-scattering off two dimensional photonic crystal structures made of silicon and reconstruct geometrical parameters.}, language = {en} } @article{HammerschmidtHerrmannPomplunetal.2016, author = {Hammerschmidt, Martin and Herrmann, Sven and Pomplun, Jan and Burger, Sven and Schmidt, Frank}, title = {Model order reduction for the time-harmonic Maxwell equation applied to complex nanostructures}, volume = {9742}, journal = {Proc. SPIE}, doi = {10.1117/12.2212367}, pages = {97420M}, year = {2016}, abstract = {Fields such as optical metrology and computational lithography require fast and efficient methods for solving the time-harmonic Maxwell's equation. Highly accurate geometrical modelling and numerical accuracy at low computational costs are a prerequisite for any simulation study of complex nano-structured photonic devices. We present a reduced basis method (RBM) for the time-harmonic electromagnetic scattering problem based on the hp-adaptive finite element solver JCMsuite capable of handling geometric and non-geometric parameter dependencies allowing for online evaluations in milliseconds. We apply the RBM to compute light-scattering at optical wavelengths of periodic arrays of fin field-effect transistors (FinFETs) where geometrical properties such as the width and height of the fin and gate can vary in a large range.}, language = {en} } @misc{GutscheLaeuterSchmidt2016, author = {Gutsche, Philipp and L{\"a}uter, Matthias and Schmidt, Frank}, title = {Parameter-dependent Parallel Block Sparse Arnoldi and D{\"o}hler Algorithms on Distributed Systems}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-58202}, year = {2016}, abstract = {We summarize the basics and first results of the analyses within our ZIB Bridge Project and give an outlook on further studies broadening the usage of hardware acceleration within the Finite Element Method (FEM) based solution of Maxwell's equations.}, language = {en} } @article{HammerschmidtHerrmannPomplunetal.2016, author = {Hammerschmidt, Martin and Herrmann, Sven and Pomplun, Jan and Burger, Sven and Schmidt, Frank}, title = {Reduced basis method for electromagnetic scattering problem: a case study for FinFETs}, volume = {48}, journal = {Optical and Quantum Electronics}, doi = {10.1007/s11082-016-0530-1}, pages = {250}, year = {2016}, abstract = {Optical 3D simulations in many-query and real-time contexts require new solution strategies. We study an adaptive, error controlled reduced basis method for solving parametrized time-harmonic optical scattering problems. Application fields are, among others, design and optimization problems of nano-optical devices as well as inverse problems for parameter reconstructions occurring e. g. in optical metrology. The reduced basis method pre- sented here relies on a finite element modeling of the scattering problem with parametrization of materials, geometries and sources.}, language = {en} } @incollection{Schmidt2017, author = {Schmidt, Frank}, title = {Photonics}, booktitle = {Handbook of Optoelectronic Device Modeling and Simulation}, editor = {Piprek, Joachim}, publisher = {CRC Press}, isbn = {9781498749381}, year = {2017}, language = {en} } @misc{SchmidtFrieseZschiedrichetal.2000, author = {Schmidt, Frank and Friese, Tilmann and Zschiedrich, Lin and Deuflhard, Peter}, title = {Adaptive Multigrid Methods for the Vectorial Maxwell Eigenvalue Problem for Optical Waveguide Design}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-6228}, number = {00-54}, year = {2000}, abstract = {This paper has been motivated by the need for a fast robust adaptive multigrid method to solve the vectorial Maxwell eigenvalue problem arising from the design of optical chips. Our nonlinear multigrid methods are based on a previous method for the scalar Helmholtz equation, which must be modified to cope with the null space of the Maxwell operator due to the divergence condition. We present two different approaches. First, we present a multigrid algorithm based on an edge element discretization of time-harmonic Maxwell's equations, including the divergence condition. Second, an explicit elimination of longitudinal magnetic components leads to a nodal discretization known to avoid discrete \emph{spurious modes} also and a vectorial eigenvalue problem, for which we present a multigrid solver. Numerical examples show that the edge element discretization clearly outperforms the nodal element approach.}, language = {en} } @misc{HohageSchmidtZschiedrich2001, author = {Hohage, Thorsten and Schmidt, Frank and Zschiedrich, Lin}, title = {Solving time-harmonic scattering problems based on the condition: Theory}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-6279}, number = {01-01}, year = {2001}, abstract = {The pole condition is a general concept for the theoretical analysis and the numerical solution of a variety of wave propagation problems. It says that the Laplace transform of the physical solution in radial direction has no poles in the lower complex half-plane. In the present paper we show that for the Helmholtz equation with a radially symmetric potential the pole condition is equivalent to Sommerfeld's radiation condition. Moreover, a new representation formula based on the pole condition is derived and used to prove existence, uniqueness and asymptotic properties of solutions. This lays the foundations of a promising new algorithm to solve time-harmonic scattering problems numerically and provides a new approach for analyzing existing algorithms such as the Perfectly Matched Layer (PML) method and the Bayliss-Gunzburger-Turkel (BGT) algorithm.}, language = {en} } @misc{HohageSchmidtZschiedrich2001, author = {Hohage, Thorsten and Schmidt, Frank and Zschiedrich, Lin}, title = {Solving time-harmonic scattering problems based on the pole condition: Convergence of the PML method}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-6494}, number = {01-23}, year = {2001}, abstract = {In this paper we study the PML method for Helmholtz-type scattering problems with radially symmetric potential. The PML method consists in surrounding the computational domain by a \textbf{P}erfectly \textbf{M}atched sponge \textbf{L}ayer. We prove that the approximate solution obtained by the PML method converges exponentially fast to the true solution in the computational domain as the thickness of the sponge layer tends to infinity. This is a generalization of results by Lassas and Somersalo based on boundary integral eqaution techniques. Here we use techniques based on the pole condition instead. This makes it possible to treat problems without an explicitly known fundamental solution.}, language = {en} } @misc{HohageSchmidtZschiedrich2002, author = {Hohage, Thorsten and Schmidt, Frank and Zschiedrich, Lin}, title = {A new method for the solution of scattering problems}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-6683}, number = {02-01}, year = {2002}, abstract = {We present a new efficient algorithm for the solution of direct time-harmonic scattering problems based on the Laplace transform. This method does not rely on an explicit knowledge of a Green function or a series representation of the solution, and it can be used for the solution of problems with radially symmetric potentials and problems with waveguides. The starting point is an alternative characterization of outgoing waves called \emph{pole condition}, which is equivalent to Sommerfeld's radiation condition for problems with radially symmetric potentials. We obtain a new representation formula, which can be used for a numerical evaluation of the exterior field in a postprocessing step. Based on previous theoretical studies, we discuss the numerical realization of our algorithm and compare its performance to the PML method.}, language = {en} } @misc{HohageSchmidt2002, author = {Hohage, Thorsten and Schmidt, Frank}, title = {On the Numerical Solution of Nonlinear Schr{\"o}dinger type equations in fiber optics}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-6715}, number = {02-04}, year = {2002}, abstract = {The aim of this paper is to develop fast methods for the solution of nonlinear Schr{\"o}dinger type equations in fiber optics. Using the method of lines we have to solve a stiff system of ordinary differential equations where the eigenvalues of the Jacobian are close to the imaginary axis. This is usually done by a Split Step method. Here we consider the extrapolation of Split Step methods with adaptive order and step size control. For more complicated nonlinearities, in particular stimulated Raman scattering, Split Step methods are less efficient since symmetry is either destroyed or requires much additional effort. In this case we use implicit Runge Kutta formulas of Gauß type. The key point for the efficient implementation of these methods is that the system of nonlinear algebraic equations can be solved without setting up the Jacobian. The proposed methods are compared to other methods, in particular exponential integrators, the method of Marcuse, and the method of Blow and Wood.}, language = {en} } @misc{RuprechtSchaedleSchmidtetal.2007, author = {Ruprecht, Daniel and Sch{\"a}dle, Achim and Schmidt, Frank and Zschiedrich, Lin}, title = {Transparent boundary conditons for time-dependent problems}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-9558}, number = {07-12}, year = {2007}, abstract = {A new approach to derive transparent boundary conditions (TBCs) for wave, Schr{\"o}dinger, heat and drift-diffusion equations is presented. It relies on the pole condition and distinguishes between physical reasonable and unreasonable solutions by the location of the singularities of the spatial Laplace transform of the exterior solution. To obtain a numerical algorithm, a M{\"o}bius transform is applied to map the Laplace transform onto the unit disc. In the transformed coordinate the solution is expanded into a power series. Finally, equations for the coefficients of the power series are derived. These are coupled to the equation in the interior, and yield transparent boundary conditions. Numerical results are presented in the last section, showing that the error introduced by the new approximate TBCs decays exponentially in the number of coefficients.}, language = {en} } @inproceedings{SchemberaWuebbelingKleikampetal.2025, author = {Schembera, Bj{\"o}rn and W{\"u}bbeling, Frank and Kleikamp, Hendrik and Schmidt, Burkhard and Shehu, Aurela and Reidelbach, Marco and Biedinger, Christine and Fiedler, Jochen and Koprucki, Thomas and Iglezakis, Dorothea and G{\"o}ddeke, Dominik}, title = {Towards a Knowledge Graph for Models and Algorithms in Applied Mathematics}, volume = {2331}, booktitle = {Metadata and Semantic Research. MTSR 2024}, publisher = {Springer Nature Switzerland}, address = {Cham}, isbn = {9783031819735}, issn = {1865-0929}, doi = {10.1007/978-3-031-81974-2_8}, pages = {95 -- 109}, year = {2025}, abstract = {Mathematical models and algorithms are an essential part of mathematical research data, as they are epistemically grounding numerical data. To make this research data FAIR, we present how two previously distinct ontologies, MathAlgoDB for algorithms and MathModDB for models, were merged and extended into a living knowledge graph as the key outcome. This was achieved by connecting the ontologies through computational tasks that correspond to algorithmic tasks. Moreover, we show how models and algorithms can be enriched with subject-specific metadata, such as matrix symmetry or model linearity, essential for defining workflows and determining suitable algorithms. Additionally, we propose controlled vocabularies to be added, along with a new class that differentiates base quantities from specific use case quantities. We illustrate the capabilities of the developed knowledge graph using two detailed examples from different application areas of applied mathematics, having already integrated over 250 research assets into the knowledge graph.}, language = {en} } @inproceedings{SchemberaWuebbelingKleikampetal.2023, author = {Schembera, Bj{\"o}rn and W{\"u}bbeling, Frank and Kleikamp, Hendrik and Biedinger, Christine and Fiedler, Jochen and Reidelbach, Marco and Shehu, Aurela and Schmidt, Burkhard and Koprucki, Thomas and Iglezakis, Dotothea and G{\"o}ddeke, Dominik}, title = {Ontologies for Models and Algorithms in Applied Mathematics and Related Disciplines}, booktitle = {Metadata and Semantic Research - MTSR 2023}, edition = {Communications in Computer and Information Science}, publisher = {Springer Nature Switzerland}, address = {Cham}, arxiv = {http://arxiv.org/abs/2310.20443}, doi = {10.1007/978-3-031-65990-4_14}, pages = {161 -- 168}, year = {2023}, abstract = {In applied mathematics and related disciplines, the modeling-simulation-optimization workflow is a prominent scheme, with mathematical models and numerical algorithms playing a crucial role. For these types of mathematical research data, the Mathematical Research Data Initiative has developed, merged and implemented ontologies and knowledge graphs. This contributes to making mathematical research data FAIR by introducing semantic technology and documenting the mathematical foundations accordingly. Using the concrete example of microfracture analysis of porous media, it is shown how the knowledge of the underlying mathematical model and the corresponding numerical algorithms for its solution can be represented by the ontologies.}, language = {en} } @article{SchemberaWuebbelingKopruckietal.2023, author = {Schembera, Bj{\"o}rn and W{\"u}bbeling, Frank and Koprucki, Thomas and Biedinger, Christine and Reidelbach, Marco and Schmidt, Burkhard and G{\"o}ddeke, Dominik and Fiedler, Jochen}, title = {Building Ontologies and Knowledge Graphs for Mathematics and its Applications}, volume = {1}, journal = {Proceedings of the Conference on Research Data Infrastructure}, publisher = {TIB Open Publishing}, issn = {2941-296X}, doi = {10.52825/cordi.v1i.255}, year = {2023}, abstract = {Ontologies and knowledge graphs for mathematical algorithms and models are presented, that have been developed by the Mathematical Research Data Initiative. This enables FAIR data handling in mathematics and the applied disciplines. Moreover, challenges of harmonization during the ontology development are discussed.}, language = {en} } @article{LangHelfmeierStefanowskietal.2020, author = {Lang, Annemarie and Helfmeier, Sarah and Stefanowski, Jonathan and Kuppe, Aditi and Sunkara, Vikram and Pfeiffenberger, Moritz and Wolter, Angelique and Damerau, Alexandra and Hemmati-Sadeghi, Shabnam and Ringe, Jochen and Haag, Rainer and Hauser, Anja E. and L{\"o}hning, Max and Perka, Carsten and Duda, Georg and Hoff, Paula and Schmidt-Bleek, Katharina and Gaber, Timo and Buttgereit, Frank}, title = {HIF-stabilization prevents delayed fracture healing}, journal = {bioarxiv}, doi = {10.1101/2020.07.02.182832}, year = {2020}, language = {en} } @article{SchemberaWuebbelingShehuetal.2025, author = {Schembera, Bj{\"o}rn and W{\"u}bbeling, Frank and Shehu, Aurela and Biedinger, Christine and Fiedler, Jochen and Reidelbach, Marco and Schmidt, Burkhard and Ferrer, Eloi and Koprucki, Thomas}, title = {FAIR Representation of Mathematical Research Data: MathModDB and MathAlgoDB as Knowledge Graphs for Mathematical Models and Numerical Algorithms}, journal = {2nd Conference on Research Data Infrastructure (CoRDI)}, doi = {10.5281/zenodo.16735911}, year = {2025}, language = {en} }