TY - CHAP A1 - Barth, Carlo A1 - Roder, Sebastian A1 - Brodoceanu, Daniel A1 - Kraus, Tobias A1 - Burger, Sven A1 - Hammerschmidt, Martin A1 - Schmidt, Frank A1 - Becker, Christiane T1 - Increased fluorescence of PbS quantum dots on photonic crystal slab structures T2 - Proc. Europ. Opt. Soc. Ann. Meet. 2016 (EOSAM) Y1 - 2016 SN - 978-1-5108-4796-5 SP - 181 ER - TY - CHAP A1 - Hammerschmidt, Martin A1 - Barth, Carlo A1 - Burger, Sven A1 - Becker, Christiane A1 - Schmidt, Frank T1 - Determining 2D photonic crystal geometries from reflectance spectra with a reduced basis method T2 - Proc. Europ. Opt. Soc. Ann. Meet. 2016 (EOSAM) Y1 - 2016 SN - 978-1-5108-4796-5 SP - 281 ER - TY - CHAP A1 - Jäger, Klaus A1 - Hammerschmidt, Martin A1 - Köppel, Grit A1 - Burger, Sven A1 - Becker, Christiane T1 - On Accurate Simulations of Thin-Film Solar Cells With a Thick Glass Superstrate T2 - Light, Energy and the Environment 2016 Y1 - 2016 U6 - https://doi.org/10.1364/PV.2016.PM3B.5 SP - PM3B.5 ER - TY - CHAP A1 - Jäger, Klaus A1 - Barth, Carlo A1 - Hammerschmidt, Martin A1 - Herrmann, Sven A1 - Burger, Sven A1 - Schmidt, Frank A1 - Becker, Christiane ED - European Society for Quantum Solar Energy Conversion, T1 - Sinusoidal Nanotextures for Enhanced Light Management in Thin-Film Solar Cells T2 - 28th Workshop on Quantum Solar Energy Conversion - (QUANTSOL) Y1 - 2016 ER - TY - JOUR A1 - Barth, Carlo A1 - Probst, Jürgen A1 - Herrmann, Sven A1 - Hammerschmidt, Martin A1 - Becker, Christiane T1 - Numerical characterization of symmetry properties for photonic crystals with hexagonal lattice JF - Proc. SPIE N2 - We present a numerical method to characterize the symmetry properties of photonic crystal (PhC) modes based on field distributions, which themselves can be obtained numerically. These properties can be used to forecast specific features of the optical response of such systems, e.g. which modes are allowed to couple to external radiation fields. We use 2D PhCs with a hexagonal lattice of holes in dielectric as an example and apply our technique to reproduce results from analytical considerations. Further, the method is extended to fully vectorial problems in view of 3D PhCs and PhC slabs, its functionality is demonstrated using test cases and, finally, we provide an efficient implementation. The technique can thus readily be applied to output data of all band structure computation methods or even be embedded – gaining additional information about the mode symmetry. Y1 - 2016 U6 - https://doi.org/10.1117/12.2227094 VL - 9885 SP - 988506 ER - TY - JOUR A1 - Jäger, Klaus A1 - Köppel, Grit A1 - Barth, Carlo A1 - Hammerschmidt, Martin A1 - Herrmann, Sven A1 - Burger, Sven A1 - Schmidt, Frank A1 - Becker, Christiane T1 - Sinusoidal gratings for optimized light management in c-Si thin-film solar cells JF - Proc. SPIE Y1 - 2016 U6 - https://doi.org/10.1117/12.2225459 VL - 9898 SP - 989808 ER - TY - THES A1 - Hammerschmidt, Martin T1 - Optical simulation of complex nanostructured solar cells with a reduced basis method N2 - Simulations of optical processes and complex nanostructured devices have become omnipresent in recent years in several fields of current research and industrial applications, not limited to the field of photovoltaics. Devices or processes are optimized with respect to a certain objective where the underlying physical processes are described by partial differential equations. In photovoltaics and photonics electromagnetic fields are investigated which are governed by Maxwell’s equations. In this thesis a reduced basis method for the solution of the parameter dependent electromagnetic scattering problem with arbitrary parameters is developed. The method is developed with the specific challenges arising in optical simulations of thin-film silicon solar cells in mind. These are large in domain size and have a complex three-dimensional structure, making optimization tasks infeasible if high-accuracy of the electromagnetic field solution is required. The application of the empirical interpolation methods allows to expand an arbitrary parameter dependence affinely. Thus not only geometries, but also material tensors and source fields can be parameterized. Additionally, the required non-linear post-processing steps of the electromagnetic field to derive energy fluxes or volume absorption are addressed. The reduced basis method allows to reduce the computational costs by orders of magnitude compared to efficient finite element solvers. In addition, an efficient tailored domain decomposition algorithm is presented to model incoherent layers or illuminations in optical systems efficiently. This is of particular interest for solar cells in superstrate configuration where the absorber is illuminated through a glass substrate. The developed methods are employed in application examples taken from collaborations with experimentalists active in the joint lab “BerOSE” (Berlin Joint Lab for Optical Simulations for Energy Research). The optical model of a thin-film silicon multi-junction with incoherent light-trapping is characterized in great detail. The computational gains through hybrid, hp adaptive finite elements are studied and the incoherent domain decomposition algorithm is applied to model a more realistic light-trapping by the glass substrate. The numerical examples of a hexagonal nano-hole array and multi-junction silicon solar cell with a tunable intermediate reflector layer show that the reduced basis method is well suited as a forward solver for modeling and optimization tasks arising in photovoltaics and photonics. Reduced models for illumination and geometric parameters are built providing up to five orders of magnitude savings in computational costs. Resonance phenomena present in the nano-hole array example are detected and the model adapts itself automatically. KW - reduced basis method; model reduction; electromagnetics; photonics; solar cells; nanooptics; Maxwells equations; incoherence Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:188-fudissthesis000000102429-1 UR - http://www.diss.fu-berlin.de/diss/receive/FUDISS_thesis_000000102429 ER - TY - GEN A1 - Hammerschmidt, Martin A1 - Herrmann, Sven A1 - Burger, Sven A1 - Pomplun, Jan A1 - Schmidt, Frank T1 - Reduced basis method for the optimization of nano-photonic devices N2 - 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. T3 - ZIB-Report - 16-10 KW - reduced basis method KW - model reduction KW - optical critical dimension metrology KW - electromagnetic field solver Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-57556 SN - 1438-0064 ER - TY - GEN A1 - Hammerschmidt, Martin A1 - Herrmann, Sven A1 - Pomplun, Jan A1 - Burger, Sven A1 - Schmidt, Frank T1 - Model order reduction for the time-harmonic Maxwell equation applied to complex nanostructures T2 - Proc. SPIE N2 - 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. T3 - ZIB-Report - 16-05 KW - reduced basis method KW - finite element method KW - rigorous optical modeling KW - reduced order models KW - electromagnetic field solver Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-57239 SN - 1438-0064 VL - 9742 SP - 97420M ER - TY - GEN A1 - Hammerschmidt, Martin A1 - Barth, Carlo A1 - Pomplun, Jan A1 - Burger, Sven A1 - Becker, Christiane A1 - Schmidt, Frank T1 - Reconstruction of photonic crystal geometries using a reduced basis method for nonlinear outputs N2 - 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. T3 - ZIB-Report - 16-06 KW - finite element method KW - rigorous optical modeling KW - photonic crystals KW - reduced basis method KW - parameter estimation KW - optical metrology Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-57249 SN - 1438-0064 ER -