A5101676008- Physics of Superconductivity and Magnetism
- Superconductivity in MgB2 and Alloys
- Superconducting Materials and Applications
- Spectroscopy and Quantum Chemical Studies
- HVDC Systems and Fault Protection
- Magnetic properties of thin films
- Advanced Condensed Matter Physics
- Quantum optics and atomic interactions
- Magnetic and transport properties of perovskites and related materials
- ZnO doping and properties
- Advancements in Photolithography Techniques
- Optical Coatings and Gratings
- Copper Interconnects and Reliability
- Electron and X-Ray Spectroscopy Techniques
- Magneto-Optical Properties and Applications
- Advanced X-ray Imaging Techniques
- Material Dynamics and Properties
- Mechanical and Optical Resonators
- Solid-state spectroscopy and crystallography
- Photochemistry and Electron Transfer Studies
- High-pressure geophysics and materials
- Electronic and Structural Properties of Oxides
- Superconducting and THz Device Technology
- Nuclear materials and radiation effects
- Wireless Networks and Protocols
ThyssenKrupp (Germany)
2021-2023
Thyssenkrupp (Slovakia)
2021
Theva (Germany)
2012-2021
Carl Zeiss (Germany)
2018-2020
CAS Software (Germany)
2018
University of Bayreuth
2002-2007
Nokia (United States)
2007
Technical University of Munich
2001-2006
University of Stuttgart
1996-2003
Max Planck Society
1989-1996
The infrared reflectivity of sintered ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathrm{\ensuremath{\delta}}}$, prepared under carefully controlled oxidation conditions, has been measured between 20 and 10 000 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ at temperatures 300 K. In this paper we analyze in detail the temperature- frequency-dependent far-infrared part spectrum. A Kramers-Kronig analysis allows us to compare phonon spectra with lattice-dynamical...
Abstract The main aim of the EU H2020 project EcoSwing was to demonstrate a technical readiness level 6–7 for high-temperature superconducting (HTS) technology operating in wind generator. To reach this goal, full-scale synchronous HTS generator successfully designed, built and field-tested 3.6 MW turbine. has rotor with 40 coils 1.4 m long. required >20 km coated conductor produced within project’s time schedule. All were tested prior assembly, >90% them behaving as expected. thus...
High temperature superconducting (HTS) technologies are expected to be a key enabler for lightweight and cost-effective direct-drive (DD) trains large wind turbines. This paper reports the designing basic experimental validation of world's first full-scale DD HTS generator demonstrated on commercial turbine. The has its rotor with an field winding working below 30 K, which is achieved by using off-the-shelf Gifford-McMahon cryocoolers. stator essentially conventional, except that armature...
High temperature superconducting (HTS) generators could enable a lightweight and cost-effective direct drive (DD) wind turbines with large power ratings. The EU-funded EcoSwing project successfully demonstrated the world's first full-scale MW-class HTS generator on commercial DD turbine. This paper focuses commissioning of campaigns, including rotor cool-down, excitation field winding, production generator, are presented in paper. In testing period, was grid-connected for more than 650 hours...
High voltage direct current super-grids are one attractive solution for the transmission of bulk power renewable electricity over long distances. Their protection is still an issue and superconducting fault limiters (SCFCL) offer perspectives. However, actual tapes not yet properly designed operation at high voltages (>100 kV): The electric field developed during limitation too low (approximately 50 V/m ms) limiter requires lengths tape. European project FASTGRID aims improving properties...
Recent experiments have shown that reversible effects of strain on the critical current density and flux pinning strength in high-temperature superconductor Bi2Sr2Ca2Cu3Ox can be explained entirely by pressure dependence its temperature. Such a correlation is less simple for RE–Ba2Cu3O7 − δ (RE = rare earth) superconductors, part because in-plane temperature highly anisotropic. Here, we make qualitative between uniaxial effect coated conductors taking crystallography texture superconducting...
DyBa2Cu3O7−x (DyBCO) films with MgO buffer layers were grown on Hastelloy substrates by inclined substrate deposition (ISD). An almost linear increase of the critical current DyBCO film thickness was observed. A maximum 1018 cm−1 measured for a 5.9 μm thickness, yielding density 1.7 MA cm−2 at 77 K and self-field. Transmission electron microscopy (TEM) yielded highly biaxially textured all thicknesses and, thus, no significant decrease occurs thickness. ISD yields non-zero component growth...
The EU-funded EcoSwing project addresses the world's first full-scale direct-drive (DD) high temperature superconducting (HTS) wind turbine generator. Before generator was installed on a commercial turbine, had been tested ground at Dynamic Nacelle Testing Laboratory (DyNaLab) in Fraunhofer Institute for Wind Energy Systems (IWES), serving as an experimental validation of design. This article is centered testing HTS generator, which includes corresponding tests validating generator's...
Next-generation extreme ultraviolet (EUV) systems with numerical apertures of 0.55 have the potential to provide sub-8-nm half-pitch resolution. The increased importance stochastic effects at smaller feature sizes places further demands on scanner and mask high contrast images. We use rigorous diffraction imaging simulation understand impact EUV absorber identify most appropriate optical parameters for NA imaging. Simulations various cases material options indicate two main types solutions:...
We observe critical behavior near ${\mathit{T}}_{\mathit{c}}$ in the infrared reflectivity of c-axis-oriented ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathit{x}}$ films prepared with pulsed situ laser deposition. From comparison theoretical spectra we show that observed is excellent agreement a phenomenological two-fluid model and strong disagreement standard BCS theory. demonstrate superconducting charge carrier density relevant order parameter...
We demonstrate that the statistical behavior of random line shapes single tetra-tert-butylterrylene chromophores embedded in an amorphous polyisobutylene matrix at T=2 K is described by Lévy statistics as predicted theoretically Barkai, Silbey, and Zumofen [Phys. Rev. Lett. 84, 5339 (2000)]. This a manifestation long-range interaction between two-level systems glass molecule. A universal amplitude ratio investigated, which shows standard tunneling model assumptions are compatible with...
We present a far-infrared study of ceramic superconductors the $M{\mathrm{Ba}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7}$ family with $M=\mathrm{Dy}$, ${\mathrm{Sm}}_{0.5}$${\mathrm{Ho}}_{0.5}$, and ${\mathrm{Sm}}_{0.5}$${\mathrm{Y}}_{0.5}$. Emphasis is placed on determination position superconducting energy gap ${E}_{g}$ its temperature dependence. find that for all compositions studied $\frac{{E}_{g}}{{k}_{B}}{T}_{c}\ensuremath{\approx}3.2\ifmmode\pm\else\textpm\fi{}0.3$. also indications...
We report the first measurement of density states low-energy vibrational excitations in a disordered solid via single-molecule (SM) spectroscopy. Optical spectra many single tetra-tert-butylterrylene (TBT) molecules embedded to amorphous polyisobutylene (PIB) as spectral probes were recorded at low temperatures. The T dependences SM linewidths showed broad distribution local frequencies vibrations under study. obtained was compared with "Boson peak" pure PIB measured [R. Inoue, J. Chem....
The current transport capability of YBa <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> Cu xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> O xmlns:xlink="http://www.w3.org/1999/xlink">7-x</sub> (YBCO) based coated conductors (CCs) is mainly limited by two features: the grain boundaries used textured template, which are transferred into superconducting film through buffer layers, and ability to pin magnetic flux lines incorporation...
The photoluminescence spectrum of melt-grown GaSe single crystals was investigated with a confocal Raman microscope equipped HeNe laser. Three luminescence bands different intensity were observed, which are mainly located to the blue laser line. signals show quadratic dependence on excitation intensity. effect is interpreted as second-harmonic generation in strongly optically nonlinear material followed by electrons into conduction band and emission from direct-gap Wannier excitons. relative...
This paper reviews the Alcatel-Lucent Universal Mobile Telecommunications System (UMTS) base station router (BSR)—a radio access network (RAN) and core (CN) in a single element. While typical cellular UMTS networks are built from plethora of elements maintained hierarchical fashion, BSR combines all functions Moreover, can be considered wireless edge that bridges between cellular-specific transmissions IP networks. Integrating RAN functionality element presents following technical...
Abstract High‐speed Maglev is a cutting‐edge technology brought back into the focus of research by plans Chinese government for development new 600 km/h train. A Chinese‐German cooperation with industrial and academic partners has been established to pursue this ambitious goal bring together experts from multiple disciplines. This contribution presents joint work achievements CRRC Qingdao Sifang, thyssenkrupp Transrapid, CDFEB, ITM University Stuttgart, regarding in field high‐speed systems....
The critical current anisotropy of a GdBa2Cu3O7 (GdBCO) coated conductor (CC) was investigated. MgO buffer layer grown by the inclined substrate deposition (ISD) technique leading to tilted c-axis growth GdBCO 24° from tape normal. Jc measured in two directions: longitudinal and transverse tape. self-field 2 μm thick 1.3 MA cm−2 0.88 at 77 K directions, respectively. 30% lower value direction results flow across weakly superconducting GdBCO. peak Jc-anisotropy corresponding intrinsic pinning...