@article{33484, abstract = {{We study the DC conductivity in potassium titanyl phosphate (KTiOPO4, KTP) and its isomorphs KTiOAsO4 (KTA) and Rb1%K99%TiOPO4 (RKTP) and introduce a method by which to reduce the overall ionic conductivity in KTP by a potassium nitrate treatment. Furthermore, we create so-called gray tracking in KTP and investigate the ionic conductivity in theses areas. A local unintended reduction of the ionic conductivity is observed in the gray-tracked regions, which also induce additional optical absorption in the material. We show that a thermal treatment in an oxygen-rich atmosphere removes the gray tracking and brings the ionic conductivity as well as the optical transmission back to the original level. These studies can help to choose the best material and treatment for specific applications.}}, author = {{Padberg, Laura and Quiring, Viktor and Bocchini, Adriana and Santandrea, Matteo and Gerstmann, Uwe and Schmidt, Wolf Gero and Silberhorn, Christine and Eigner, Christof}}, issn = {{2073-4352}}, journal = {{Crystals}}, pages = {{1359}}, title = {{{DC Ionic Conductivity in KTP and Its Isomorphs: Properties, Methods for Suppression, and Its Connection to Gray Tracking}}}, doi = {{10.3390/cryst12101359}}, volume = {{12}}, year = {{2022}}, } @inproceedings{33485, author = {{Dechert, Christopher and Kenig, Eugeny}}, booktitle = {{Proceedings of the 12th international conference Distillation & Absorption 2022}}, location = {{Toulouse, France}}, title = {{{CFD-Based Investigation of the Packing Microstructure Influence on Droplet Behavior and Film Flow}}}, year = {{2022}}, } @article{33990, abstract = {{Deep neural networks (DNNs) are penetrating into a broad spectrum of applications and replacing manual algorithmic implementations, including the radio frequency communications domain with classical signal processing algorithms. However, the high throughput (gigasamples per second) and low latency requirements of this application domain pose a significant hurdle for adopting computationally demanding DNNs. In this article, we explore highly specialized DNN inference accelerator approaches on field-programmable gate arrays (FPGAs) for RadioML modulation classification. Using an automated end-to-end flow for the generation of the FPGA solution, we can easily explore a spectrum of solutions that optimize for different design targets, including accuracy, power efficiency, resources, throughput, and latency. By leveraging reduced precision arithmetic and customized streaming dataflow, we demonstrate a solution that meets the application requirements and outperforms alternative FPGA efforts by 3.5x in terms of throughput. Against modern embedded graphics processing units (GPUs), we measure >10x higher throughput and >100x lower latency under comparable accuracy and power envelopes.}}, author = {{Jentzsch, Felix and Umuroglu, Yaman and Pappalardo, Alessandro and Blott, Michaela and Platzner, Marco}}, journal = {{IEEE Micro}}, number = {{6}}, pages = {{125--133}}, publisher = {{IEEE}}, title = {{{RadioML Meets FINN: Enabling Future RF Applications With FPGA Streaming Architectures}}}, doi = {{10.1109/MM.2022.3202091}}, volume = {{42}}, year = {{2022}}, } @article{26627, abstract = {{Many-body perturbation theory based on density-functional theory calculations is used to determine the quasiparticle band structures and the dielectric functions of the isomorphic ferroelectrics rubidium titanyl phosphate (RbTiOPO4) and potassium titanyl arsenide (KTiOAsO4). Self-energy corrections of more than 2 eV are found to widen the transport band gaps of both materials considerably to 5.3 and 5.2 eV, respectively. At the same time, both materials are characterized by strong exciton binding energies of 1.4 and 1.5 eV, respectively. The solution of the Bethe-Salpeter equation based on the quasiparticle energies results in onsets of the optical absorption within the range of the measured data.}}, author = {{Neufeld, Sergej and Schindlmayr, Arno and Schmidt, Wolf Gero}}, issn = {{2515-7639}}, journal = {{Journal of Physics: Materials}}, number = {{1}}, publisher = {{IOP Publishing}}, title = {{{Quasiparticle energies and optical response of RbTiOPO4 and KTiOAsO4}}}, doi = {{10.1088/2515-7639/ac3384}}, volume = {{5}}, year = {{2022}}, } @article{37656, author = {{Glahn, Luis Joel and Ruiz Alvarado, Isaac Azahel and Neufeld, Sergej and Zare Pour, Mohammad Amin and Paszuk, Agnieszka and Ostheimer, David and Shekarabi, Sahar and Romanyuk, Oleksandr and Moritz, Dominik Christian and Hofmann, Jan Philipp and Jaegermann, Wolfram and Hannappel, Thomas and Schmidt, Wolf Gero}}, issn = {{0370-1972}}, journal = {{physica status solidi (b)}}, keywords = {{Condensed Matter Physics, Electronic, Optical and Magnetic Materials}}, number = {{11}}, publisher = {{Wiley}}, title = {{{Clean and Hydrogen‐Adsorbed AlInP(001) Surfaces: Structures and Electronic Properties}}}, doi = {{10.1002/pssb.202200308}}, volume = {{259}}, year = {{2022}}, } @article{37710, author = {{Ruiz Alvarado, Isaac Azahel and Schmidt, Wolf Gero}}, issn = {{2470-1343}}, journal = {{ACS Omega}}, keywords = {{General Chemical Engineering, General Chemistry}}, number = {{23}}, pages = {{19355--19364}}, publisher = {{American Chemical Society (ACS)}}, title = {{{Water/InP(001) from Density Functional Theory}}}, doi = {{10.1021/acsomega.2c00948}}, volume = {{7}}, year = {{2022}}, } @article{37681, author = {{Moritz, Dominik Christian and Ruiz Alvarado, Isaac Azahel and Zare Pour, Mohammad Amin and Paszuk, Agnieszka and Frieß, Tilo and Runge, Erich and Hofmann, Jan P. and Hannappel, Thomas and Schmidt, Wolf Gero and Jaegermann, Wolfram}}, issn = {{1944-8244}}, journal = {{ACS Applied Materials & Interfaces}}, keywords = {{General Materials Science}}, number = {{41}}, pages = {{47255--47261}}, publisher = {{American Chemical Society (ACS)}}, title = {{{P-Terminated InP (001) Surfaces: Surface Band Bending and Reactivity to Water}}}, doi = {{10.1021/acsami.2c13352}}, volume = {{14}}, year = {{2022}}, } @article{40423, abstract = {{Lewis-acid doping of organic semiconductors (OSCs) opens up new ways of p-type doping and has recently become of significant interest.}}, author = {{Bauch, Fabian and Dong, Chuan-Ding and Schumacher, Stefan}}, issn = {{2046-2069}}, journal = {{RSC Advances}}, keywords = {{General Chemical Engineering, General Chemistry}}, number = {{22}}, pages = {{13999--14006}}, publisher = {{Royal Society of Chemistry (RSC)}}, title = {{{Protonation-induced charge transfer and polaron formation in organic semiconductors doped by Lewis acids}}}, doi = {{10.1039/d2ra02032g}}, volume = {{12}}, year = {{2022}}, } @article{40425, author = {{Bathe, Thomas and Dong, Chuan-Ding and Schumacher, Stefan}}, issn = {{1089-5639}}, journal = {{The Journal of Physical Chemistry A}}, keywords = {{Physical and Theoretical Chemistry}}, number = {{13}}, pages = {{2075--2081}}, publisher = {{American Chemical Society (ACS)}}, title = {{{Microscopic Study of Molecular Double Doping}}}, doi = {{10.1021/acs.jpca.1c09179}}, volume = {{126}}, year = {{2022}}, } @article{33965, author = {{Bocchini, Adriana and Gerstmann, Uwe and Bartley, Tim and Steinrück, Hans-Georg and Henkel, Gerald and Schmidt, Wolf Gero}}, journal = {{Phys. Rev. Materials}}, pages = {{105401}}, publisher = {{American Physical Society}}, title = {{{Electrochemical performance of KTiOAsO_4 (KTA) in potassium-ion batteries from density-functional theory}}}, doi = {{10.1103/PhysRevMaterials.6.105401}}, volume = {{6}}, year = {{2022}}, } @article{31254, author = {{Bocchini, Adriana and Gerstmann, Uwe and Schmidt, Wolf Gero}}, journal = {{Phys. Rev. B}}, pages = {{205118}}, publisher = {{American Physical Society}}, title = {{{Oxygen vacancies in KTiOPO_4: Optical absorption from hybrid DFT}}}, doi = {{10.1103/PhysRevB.105.205118}}, volume = {{105}}, year = {{2022}}, } @article{27375, author = {{Schulz, Andreas Markus and Wecker, Christian and Inguva, Venkatesh and Lopatin, Alexey S. and Kenig, Eugeny Y.}}, journal = {{Chemical Engineering Science}}, location = {{Muster location}}, publisher = {{Elsevier}}, title = {{{A PLIC-based method for species mass transfer at free fluid interfaces}}}, doi = {{10.1016/j.ces.2021.117357}}, volume = {{250}}, year = {{2022}}, } @article{28942, author = {{Wecker, Christian and Schulz, Andreas Markus and Heine, Jens and Bart, Hans Jörg and Kenig, Eugeny Y.}}, journal = {{International Journal of Heat and Mass Transfer}}, publisher = {{ELSEVIER}}, title = {{{Droplet formation –a numerical investigation of liquid-liquid systems with consideration of Marangoni convection}}}, doi = {{10.1016/j.ijheatmasstransfer.2021.122465}}, volume = {{188}}, year = {{2022}}, } @article{44235, author = {{Inguva, Venkatesh and Kenig, Eugeny Y. and Perot, J. Blair}}, journal = {{Journal of Computational Physics}}, publisher = {{Elsevier}}, title = {{{A front-tracking method for two-phase flow simulation with no spurious currents}}}, volume = {{456}}, year = {{2022}}, } @article{30591, author = {{Bertling, René and Hack, M. and Ausner, I. and Horschitz, B. and Bernemann, Sören Antonius and Kenig, Eugeny}}, issn = {{0009-2509}}, journal = {{Chemical Engineering Science}}, keywords = {{Applied Mathematics, Industrial and Manufacturing Engineering, General Chemical Engineering, General Chemistry}}, publisher = {{Elsevier BV}}, title = {{{Modelling film and rivulet flows on microstructured surfaces using CFD methods}}}, doi = {{10.1016/j.ces.2021.117414}}, volume = {{251}}, year = {{2022}}, } @inproceedings{33739, abstract = {{At least 5% of questions submitted to search engines ask about cause-effect relationships in some way. To support the development of tailored approaches that can answer such questions, we construct Webis-CausalQA-22, a benchmark corpus of 1.1 million causal questions with answers. We distinguish different types of causal questions using a novel typology derived from a data-driven, manual analysis of questions from ten large question answering (QA) datasets. Using high-precision lexical rules, we extract causal questions of each type from these datasets to create our corpus. As an initial baseline, the state-of-the-art QA model UnifiedQA achieves a ROUGE-L F1 score of 0.48 on our new benchmark.}}, author = {{Bondarenko, Alexander and Wolska, Magdalena and Heindorf, Stefan and Blübaum, Lukas and Ngonga Ngomo, Axel-Cyrille and Stein, Benno and Braslavski, Pavel and Hagen, Matthias and Potthast, Martin}}, booktitle = {{Proceedings of the 29th International Conference on Computational Linguistics}}, pages = {{3296–3308}}, publisher = {{International Committee on Computational Linguistics}}, title = {{{CausalQA: A Benchmark for Causal Question Answering}}}, year = {{2022}}, } @unpublished{33493, abstract = {{Electronic structure calculations have been instrumental in providing many important insights into a range of physical and chemical properties of various molecular and solid-state systems. Their importance to various fields, including materials science, chemical sciences, computational chemistry and device physics, is underscored by the large fraction of available public supercomputing resources devoted to these calculations. As we enter the exascale era, exciting new opportunities to increase simulation numbers, sizes, and accuracies present themselves. In order to realize these promises, the community of electronic structure software developers will however first have to tackle a number of challenges pertaining to the efficient use of new architectures that will rely heavily on massive parallelism and hardware accelerators. This roadmap provides a broad overview of the state-of-the-art in electronic structure calculations and of the various new directions being pursued by the community. It covers 14 electronic structure codes, presenting their current status, their development priorities over the next five years, and their plans towards tackling the challenges and leveraging the opportunities presented by the advent of exascale computing.}}, author = {{Gavini, Vikram and Baroni, Stefano and Blum, Volker and Bowler, David R. and Buccheri, Alexander and Chelikowsky, James R. and Das, Sambit and Dawson, William and Delugas, Pietro and Dogan, Mehmet and Draxl, Claudia and Galli, Giulia and Genovese, Luigi and Giannozzi, Paolo and Giantomassi, Matteo and Gonze, Xavier and Govoni, Marco and Gulans, Andris and Gygi, François and Herbert, John M. and Kokott, Sebastian and Kühne, Thomas and Liou, Kai-Hsin and Miyazaki, Tsuyoshi and Motamarri, Phani and Nakata, Ayako and Pask, John E. and Plessl, Christian and Ratcliff, Laura E. and Richard, Ryan M. and Rossi, Mariana and Schade, Robert and Scheffler, Matthias and Schütt, Ole and Suryanarayana, Phanish and Torrent, Marc and Truflandier, Lionel and Windus, Theresa L. and Xu, Qimen and Yu, Victor W. -Z. and Perez, Danny}}, booktitle = {{arXiv:2209.12747}}, title = {{{Roadmap on Electronic Structure Codes in the Exascale Era}}}, year = {{2022}}, } @inproceedings{46193, author = {{Karp, Martin and Podobas, Artur and Kenter, Tobias and Jansson, Niclas and Plessl, Christian and Schlatter, Philipp and Markidis, Stefano}}, booktitle = {{International Conference on High Performance Computing in Asia-Pacific Region}}, publisher = {{ACM}}, title = {{{A High-Fidelity Flow Solver for Unstructured Meshes on Field-Programmable Gate Arrays: Design, Evaluation, and Future Challenges}}}, doi = {{10.1145/3492805.3492808}}, year = {{2022}}, } @unpublished{32404, abstract = {{The CP2K program package, which can be considered as the swiss army knife of atomistic simulations, is presented with a special emphasis on ab-initio molecular dynamics using the second-generation Car-Parrinello method. After outlining current and near-term development efforts with regards to massively parallel low-scaling post-Hartree-Fock and eigenvalue solvers, novel approaches on how we plan to take full advantage of future low-precision hardware architectures are introduced. Our focus here is on combining our submatrix method with the approximate computing paradigm to address the immanent exascale era.}}, author = {{Kühne, Thomas and Plessl, Christian and Schade, Robert and Schütt, Ole}}, booktitle = {{arXiv:2205.14741}}, title = {{{CP2K on the road to exascale}}}, year = {{2022}}, } @article{33226, abstract = {{A parallel hybrid quantum-classical algorithm for the solution of the quantum-chemical ground-state energy problem on gate-based quantum computers is presented. This approach is based on the reduced density-matrix functional theory (RDMFT) formulation of the electronic structure problem. For that purpose, the density-matrix functional of the full system is decomposed into an indirectly coupled sum of density-matrix functionals for all its subsystems using the adaptive cluster approximation to RDMFT. The approximations involved in the decomposition and the adaptive cluster approximation itself can be systematically converged to the exact result. The solutions for the density-matrix functionals of the effective subsystems involves a constrained minimization over many-particle states that are approximated by parametrized trial states on the quantum computer similarly to the variational quantum eigensolver. The independence of the density-matrix functionals of the effective subsystems introduces a new level of parallelization and allows for the computational treatment of much larger molecules on a quantum computer with a given qubit count. In addition, for the proposed algorithm techniques are presented to reduce the qubit count, the number of quantum programs, as well as its depth. The evaluation of a density-matrix functional as the essential part of our approach is demonstrated for Hubbard-like systems on IBM quantum computers based on superconducting transmon qubits.}}, author = {{Schade, Robert and Bauer, Carsten and Tamoev, Konstantin and Mazur, Lukas and Plessl, Christian and Kühne, Thomas}}, journal = {{Phys. Rev. Research}}, pages = {{033160}}, publisher = {{American Physical Society}}, title = {{{Parallel quantum chemistry on noisy intermediate-scale quantum computers}}}, doi = {{10.1103/PhysRevResearch.4.033160}}, volume = {{4}}, year = {{2022}}, }