@inproceedings{HammerschmidtPomplunBurgeretal.2014, author = {Hammerschmidt, Martin and Pomplun, Jan and Burger, Sven and Schmidt, Frank}, title = {Adaptive sampling strategies for effcient parameter scans in nano-photonic device simulations}, volume = {8980}, booktitle = {Proc. SPIE}, publisher = {SPIE}, doi = {10.1117/12.2036363}, pages = {89801O}, year = {2014}, language = {en} } @inproceedings{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}, volume = {8980}, booktitle = {Proc. SPIE: Physics and Simulation of Optoelectronic Devices XXII}, publisher = {SPIE}, doi = {10.1117/12.2036346}, pages = {898007}, year = {2014}, 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} } @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} } @article{HammerschmidtLockauBurgeretal.2013, author = {Hammerschmidt, Martin and Lockau, Daniel and Burger, Sven and Schmidt, Frank and Schwanke, Christoph and Kirner, Simon and Calnan, Sonya and Stannowski, Bernd and Rech, Bernd}, title = {FEM-based optical modeling of silicon thin-film tandem solar cells with randomly textured interfaces in 3D}, volume = {8620}, journal = {Proc. SPIE}, doi = {10.1117/12.2001789}, pages = {86201H}, year = {2013}, language = {en} } @inproceedings{HammerschmidtLockauBurgeretal.2012, author = {Hammerschmidt, Martin and Lockau, Daniel and Burger, Sven and Schmidt, Frank and Schwanke, Christoph and Kirner, Simon and Calnan, Sonya and Stannowski, Bernd and Rech, Bernd}, title = {3D optical modeling of thin-film a-Si/mc-Si tandem solar cells with random textured interfaces using FEM}, booktitle = {Renewable Energy and the Environment Optics and Photonics Congress}, publisher = {Optical Society of America}, doi = {10.1364/E2.2012.JM5A.15}, pages = {JM5A.15}, year = {2012}, language = {en} } @inproceedings{ZschiedrichGreinerPomplunetal.2012, author = {Zschiedrich, Lin and Greiner, Horst and Pomplun, Jan and Hammerschmidt, Martin and Burger, Sven and Schmidt, Frank}, title = {FEM simulations of light extraction from nanostructured organic light-emitting diodes}, booktitle = {Renewable Energy and the Environment Optics and Photonics Congress}, publisher = {Optical Society of America}, doi = {10.1364/SOLED.2012.LT2B.5}, pages = {LT2B.5}, year = {2012}, language = {en} }