TY - GEN AU - Jamebozorgi, Vahid AU - Rasim, Karsten AU - Schröder, Christian ID - 2760 T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft TI - Multiscale modeling and simulation of texture effects on the corrosion of stainless steel in aqueous media ER - TY - GEN AU - Bekemeier, Simon AU - Blum, Moritz AU - Caron, Luana AU - Cimiano, Philipp AU - Ell, Basil AU - Ennen, Inga AU - Feige, Michael AU - Hilbig, Thomas AU - Hütten, Andreas AU - Reiss, Günter AU - Samanta, Tapas AU - Schöning, Sonja AU - Schröder, Christian AU - Schwan, Lennart AU - Wortmann, Martin ID - 2758 T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft TI - An Ontology of Magnetocaloric Materials Research ER - TY - CONF AU - Bekemeier, Simon AU - Hilbig, Thomas AU - Nickel, Sascha AU - Yaman, Onur AU - Schröder, Christian ID - 3739 T2 - FEMS EUROMAT 2023 TI - Accelerating Knowledge Generation and Materials Discovery through Automated Digitalization Workflows ER - TY - CONF AU - Jamebozorgi, Vahid AU - Rasim, Karsten AU - Schröder, Christian ID - 3732 T2 - FEMS EUROMAT 2023 TI - Quantum chemical insight to passive layer formation and breakdown mechanisms in ferritic stainless steels ER - TY - CONF AU - Bekemeier, Simon AU - Chirkova, Alisa AU - Schröder, Christian ID - 2759 T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft TI - A high-level workflow-based approach towards the exploration of magnetocaloric Heusler alloys by automated high-throughput simulations ER - TY - JOUR AU - Schmidt, Heinz-Jürgen AU - Schröder, Christian ID - 2731 IS - 2 JF - Few-Body Systems TI - Thermodynamics of the Spin Square VL - 64 ER - TY - CONF AU - Jamebozorgi, Vahid AU - Schröder, Christian ID - 2240 T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft TI - DFT based analysis of surface reactions of stainless steels through degradation in aqueous media ER - TY - CONF AU - Bekemeier, Simon AU - Schröder, Christian ID - 2239 T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft TI - Predictive Design of Induction Coil Geometries using Neural Networks ER - TY - JOUR AB - Abstract - Molecular dynamics (MD) simulations in the canonical (NVT) and the isothermal-isobaric (NPT) ensemble using COMPASS III molecular force fields were performed to study the penetrant diffusion of water (H 2 O), hydrogen peroxide (H 2 O 2 ) and oxygen (O 2 ) in isotactic polypropylene (iPP) and hydrogen (H 2 ) in iPP and atactic polypropylene (aPP) for time intervals up to 11 ns and in the case of H 2 O 2 up to 22 ns. We found robust cluster formation in the case of H 2 O and H 2 O 2 . Further, the diffusion coefficients for all these systems were estimated by mean-square displacement analysis. Our results are consistent with previously published experimental and computational data except for the diffusion of H 2 in polypropylene where our results are one and two orders of magnitude higher, respectively. Grand Canonical Monte Carlo (GCMC) simulations were used to determine the sorption loading and saturation concentration of H 2 O, O 2 and H 2 in iPP, where we find good agreement for H 2 O with experimental results. By means of MD simulation the glass transition temperature (T g ) of iPP was estimated to 273.66 ± 4.21 K which is consistent with previously published experimental results. AU - Deckers, Fabian AU - Rasim, Karsten AU - Schröder, Christian ID - 2156 IS - 11 JF - Journal of Polymer Research SN - 1022-9760 TI - Molecular dynamics simulation of polypropylene: diffusion and sorption of H2O, H2O2, H2, O2 and determination of the glass transition temperature VL - 29 ER - TY - JOUR AU - Zhang, Hao-Lan AU - Zhai, Yuan-Qi AU - Nojiri, Hiroyuki AU - Schröder, Christian AU - Hsu, Hung-Kai AU - Chan, Yi-Tsu AU - Fu, Zhendong AU - Zheng, Yan-Zhen ID - 2108 IS - 33 JF - Journal of the American Chemical Society SN - 0002-7863 TI - {Sc Gd } Heterometallic Rings: Tunable Ring Topology for Spin-Wave Excitations VL - 144 ER - TY - JOUR AB - Abstract - The classical spin system consisting of three spins with Heisenberg interaction is an example of a completely integrable mechanical system. In this paper, we explicitly calculate thermodynamic quantities such as density of states, specific heat, susceptibility and spin autocorrelation functions. These calculations are performed (semi-)analytically and shown to agree with corresponding Monte Carlo simulations. It is shown that the thermodynamic functions depend qualitatively on the character of the system in terms of its frustration, especially w. r. t. their low temperature limit. For the long-time autocorrelation function, we find, for certain values of the coupling constants, a decay to constant values in the form of an 1/ t damped harmonic oscillation and propose a theoretical explanation. AU - Schmidt, Heinz-Jürgen AU - Schröder, Christian ID - 1828 IS - 11 JF - Zeitschrift für Naturforschung A SN - 0932-0784 TI - Thermodynamics of the classical spin triangle VL - 77 ER - TY - JOUR AB - Abstract - Equilibration of observables in closed quantum systems that are described by a unitary time evolution is a meanwhile well-established phenomenon apart from a few equally well-established exceptions. Here we report the surprising theoretical observation that integrable as well as non-integrable spin rings with nearest-neighbor or long-range isotropic Heisenberg interaction not only equilibrate but moreover also synchronize the directions of the expectation values of the individual spins. We highlight that this differs from spontaneous synchronization in quantum dissipative systems. Here, we observe mutual synchronization of local spin directions in closed systems under unitary time evolution. In our numerical simulations, we investigate the free induction decay of an ensemble of up to N = 25 quantum spins with s = 1/2 each by solving the time-dependent Schrödinger equation numerically exactly. Our findings are related to, but not fully explained by conservation laws of the system. Even if we cannot provide a full understanding of the phenomenon, it is very robust against for instance random fluctuations of the Heisenberg couplings and inhomogeneous magnetic fields. The observed synchronization is independent of whether the interaction is ferro- or antiferromagnetic. Synchronization is not observed with strong enough symmetry-breaking interactions such as the dipolar interaction. We also compare our results to closed-system classical spin dynamics which does not exhibit phase synchronization due to the lack of entanglement and since the fixed magnitude of individual classical spins effectively acts like additional N conservation laws. AU - Vorndamme, Patrick AU - Schmidt, Heinz-Jürgen AU - Schröder, Christian AU - Schnack, Jürgen ID - 1829 IS - 8 JF - New Journal of Physics TI - Observation of phase synchronization and alignment during free induction decay of quantum spins with Heisenberg interactions VL - 23 ER - TY - JOUR AB - Round magnetic nano-dots belong to the frequently investigated magnetic nanostructures since they can often reverse magnetization via a vortex state which is characterized by low stray fields, making them useful for data storage applications. Nano-rings, with an open aperture in the middle, regularly show flux-closed vortex states without a vortex core, again reducing stray fields. Here we theoretically investigate “Pac-Man” shaped iron nanostructures with varying aperture, i.e. structures ranging from a thin ring to a solid cylinder with a triangular cut. Our results show that in most cases, a vortex-like state without vortex core along the whole nanostructure occurs during magnetization reversal. Depending on the angle of the external magnetic field and the nanostructure thickness, different magnetization reversal processes have been found, including domain wall nucleation and propagation as well as small vortex states with cores. The occurrence of such special magnetic states can be attributed to the interaction of the shape anisotropy with the relatively high magneto-crystalline anisotropy of iron. Our simulations reveal the possibilities to use such structures for data storage applications as well as their importance in basic research, enabling formation of asymmetric magnetic structures beyond common onion and symmetric vortex states. AU - Bachar, Fatima-Zohra AU - Schröder, Christian AU - Ehrmann, Andrea ID - 1426 JF - Journal of Magnetism and Magnetic Materials KW - Magnetic nanostructures Micromagnetic simulation Magnetization reversal Iron Vortex state Domain walls Shape anisotropy SN - 03048853 TI - Magnetization reversal in Pac-Man shaped Fe nanostructures with varying aperture VL - 537 ER - TY - JOUR AU - Qin, Lei AU - Zhang, Hao-Lan AU - Zhai, Yuan-Qi AU - Nojiri, Hiroyuki AU - Schröder, Christian AU - Zheng, Yan-Zhen ID - 1425 IS - 4 JF - iScience SN - 25890042 TI - A giant spin molecule with ninety-six parallel unpaired electrons VL - 24 ER - TY - JOUR AU - Al Mamoori, Mohanad AU - Schröder, Christian AU - Keller, Lukas AU - Huth, Michael AU - Müller, Jens ID - 1428 IS - 1 JF - AIP Advances TI - First-order reversal curves (FORCs) of nano-engineered 3D Co-Fe structures VL - 10 ER - TY - JOUR AB - In this review article, we conceptually investigated the requirements of magnetic nanoparticles for their application in biosensing and related them to example systems of our thin-film portfolio. Analyzing intrinsic magnetic properties of different magnetic phases, the size range of the magnetic particles was determined, which is of potential interest for biosensor technology. Different e-beam lithography strategies are utilized to identify possible ways to realize small magnetic particles targeting this size range. Three different particle systems from 500 μm to 50 nm are produced for this purpose, aiming at tunable, vertically magnetized synthetic antiferromagnets, martensitic transformation in a single elliptical, disc-shaped Heusler Ni50Mn32.5Ga17.5 particle and nanocylinders of Co2MnSi-Heusler compound. Perspectively, new applications for these particle systems in combination with microfluidics are addressed. Using the concept of a magnetic on–off ratchet, the most suitable particle system of these three materials is validated with respect to magnetically-driven transport in a microfluidic channel. In addition, options are also discussed for improving the magnetic ratchet for larger particles. AU - Kappe, Daniel AU - Bondzio, Laila AU - Swager, Joris AU - Becker, Andreas AU - Büker, Björn AU - Ennen, Inga AU - Schröder, Christian AU - Hütten, Andreas ID - 1427 IS - 16 JF - Sensors TI - Reviewing Magnetic Particle Preparation: Exploring the Viability in Biosensing VL - 20 ER - TY - CONF AU - Weber, Lennart AU - Schröder, Christian AU - Schöning, Sonja ID - 1839 T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft TI - Using Non-Linear Material Properties for the Optimization of Heat Generation in Inductive Heating Applications ER - TY - CONF AU - Al Mamoori, Mohanad AU - Keller, Lukas AU - Huth, Michael AU - Schröder, Christian AU - Müller, Jens ID - 1842 T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft TI - Magnetization Reversal of Individual Three Dimensional (3D) Fe-Co Nanostructures ER - TY - CONF AU - Müller, Jens AU - Al Mamoori, Mohanad AU - Keller, Lukas AU - Huth, Michael AU - Schröder, Christian ID - 1841 T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft TI - Micro-Hall Magnetometry of FEBID-fabricated 3D magnetic nano-architectures ER - TY - CONF AU - Laas, Assja AU - Schröder, Christian ID - 1840 T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft TI - Designing non-conventional 3-D coils ER -