A5032897914- Physics of Superconductivity and Magnetism
- Magnetic properties of thin films
- Quantum and electron transport phenomena
- Advanced Condensed Matter Physics
- Theoretical and Computational Physics
- Magnetic and transport properties of perovskites and related materials
- Magneto-Optical Properties and Applications
- Superconductivity in MgB2 and Alloys
- Advanced Electron Microscopy Techniques and Applications
- Magnetic Properties and Applications
- stochastic dynamics and bifurcation
- Superconducting Materials and Applications
- Ion-surface interactions and analysis
- Characterization and Applications of Magnetic Nanoparticles
- Electronic and Structural Properties of Oxides
- Magnetic confinement fusion research
- Nonlinear Dynamics and Pattern Formation
- Particle accelerators and beam dynamics
- Diamond and Carbon-based Materials Research
- ZnO doping and properties
- Electron and X-Ray Spectroscopy Techniques
- Superconducting and THz Device Technology
- Rare-earth and actinide compounds
- Iron-based superconductors research
- Quantum, superfluid, helium dynamics
Goethe University Frankfurt
2012-2024
University of Vienna
2020-2024
Technische Universität Braunschweig
2024
Vienna Center for Quantum Science and Technology
2023
Moldova State University
2022
Innovent
2021
V. N. Karazin Kharkiv National University
2010-2020
Goethe Institute
2014
Magnonics addresses the physical properties of spin waves and utilizes them for data processing. Scalability down to atomic dimensions, operation in GHz-to-THz frequency range, utilization nonlinear nonreciprocal phenomena, compatibility with CMOS are just a few many advantages offered by magnons. Although magnonics is still primarily positioned academic domain, scientific technological challenges field being extensively investigated, proof-of-concept prototypes have already been realized...
The ultra-fast dynamics of superconducting vortices harbors rich physics generic to nonequilibrium collective systems. phenomenon flux-flow instability (FFI), however, prevents its exploration and sets practical limits for the use in various applications. To suppress FFI, a superconductor should exhibit rarely achieved combination properties: weak volume pinning, close-to-depairing critical current, fast heat removal from heated electrons. Here, we demonstrate experimentally vortex motion at...
The focused ion beam (FIB) is a powerful tool for fabrication, modification, and characterization of materials down to the nanoscale. Starting with gallium FIB, which was originally intended photomask repair in semiconductor industry, there are now many different types FIB that commercially available. These instruments use range species applied broadly science, physics, chemistry, biology, medicine, even archaeology. goal this roadmap provide an overview instrumentation, theory, techniques,...
Additive nanotechnology enable curvilinear and three-dimensional (3D) magnetic architectures with tunable topology functionalities surpassing their planar counterparts. Here, we experimentally reveal that 3D soft wireframe structures resemble compact manifolds accommodate textures of high order vorticity determined by the Euler characteristic, χ. We demonstrate self-standing tetrapods (homeomorphic to a sphere; χ = + 2) support six surface topological solitons, namely four vortices two...
Local modification of magnetic properties nanoelements is a key to design future-generation magnonic devices in which information carried and processed via spin waves. One the biggest challenges here fabricate simple miniature phase-controlling elements with broad tunability. Here, we successfully realize such spin-wave phase shifters upon single nanogroove milled by focused ion beam Co–Fe microsized waveguide. By varying groove depth in-plane bias field, continuously tune experimentally...
Performing propagating spin-wave spectroscopy of thin films at millikelvin temperatures is the next step toward realization large-scale integrated magnonic circuits for quantum applications. Here, we demonstrate propagation in a 100 nm-thick yttrium-iron-garnet (YIG) film down to 45 mK, using stripline nanoantennas deposited on YIG surface electrical excitation and detection. The clear transmission characteristics over distance 10 μ m are measured extracted group velocity saturation...
Superconducting planar nanostructures are widely used in applications, e.g., for highly sensitive magnetometers and basic research, to study finite size effects or vortex dynamics. In contrast, 3D superconducting nanostructures, despite their potential quantum information processing nanoelectronics, have been addressed only a few pioneering experiments. This is due the complexity of fabricating by conventional techniques such as electron-beam lithography scarce number materials available...
The photon count rate (PCR) of superconducting single-photon detectors made ${\mathrm{Mo}}_{x}{\mathrm{Si}}_{1\text{\ensuremath{-}}x}$ films shaped as a 2-$\ensuremath{\mu}\mathrm{m}$-wide strip and 115-nm-wide meander line is studied experimentally function the dc biasing current at different values perpendicular magnetic field. For wide strip, crossover ${I}_{\mathrm{cross}}$ observed, below which PCR increases with an increasing field above it decreases. This behavior contrasts narrow...
The dynamics of Abrikosov vortices in superconductors is usually limited to vortex velocities $v\simeq1$ km/s above which samples abruptly transit into the normal state. In Larkin-Ovchinnikov framework, near critical temperature this because a flux-flow instability triggered by reduction viscous drag coefficient due quasiparticles leaving cores. While existing theories rely upon uniform spatial distribution velocities, measured (mean) value $v$ always smaller than maximal possible one, since...
Extending nanostructures into the third dimension has become a major research avenue in modern magnetism, superconductivity, and spintronics, because of geometry-, curvature-, topology-induced phenomena. Here, we introduce Co–Fe nanovolcanoes—nanodisks overlaid by nanorings—as purpose-engineered 3D architectures for nanomagnonics, fabricated focused electron beam-induced deposition. We use both perpendicular spin-wave resonance measurements micromagnetic simulations to demonstrate that rings...
Ultrafast vortex motion has recently become a subject of extensive investigations, triggered by the fundamental question regarding ultimate speed limits for magnetic flux quanta and enhancements single-photon detectors. In this regard, current-biased quench dynamic flux-flow regime---flux-flow instability (FFI)---has turned into widely used method extraction information about relaxation quasiparticles (unpaired electrons) in superconductor. However, large times ${\ensuremath{\tau}}_{ϵ}$...
The interaction of (quasi)particles with a periodic potential arises in various domains science and engineering, such as solid-state physics, chemical communication theory. An attractive test ground to investigate this is represented by superconductors artificial pinning sites, where magnetic flux quanta (Abrikosov vortices) interact the U(r) = U(r + R) induced nanostructure. At combination microwave dc currents, fluxons act mobile probes U(r): ac component shakes vicinity their equilibrium...
Larkin and Ovchinnikov established that the viscous flow of magnetic flux quanta in current-biased superconductor films placed a perpendicular field can lose stability due to decrease vortex viscosity coefficient $\eta$ with increasing velocity vortices $v$. The dependence on $v$ leads $nonlinear$ section current-voltage ($I$-$V$) curve which ends at flux-flow instability point voltage jump highly resistive state. At same time, contradistinction nonlinear conductivity regime, jumps often...
In the majority of cases nanostructures prepared by focused electron beam induced deposition (FEBID) employing an organometallic precursor contain predominantly carbon-based ligand dissociation products. This is unfortunate with regard to using this high-resolution direct-write approach for preparation various fields, such as mesoscopic physics, micromagnetism, electronic correlations, spin-dependent transport and numerous applications. Here we present in situ cleaning obtain pure Co-FEBID...
An original spatially resolved approach is demonstrated for spin-wave spectroscopy of individual circular magnetic elements. It allows the deduction saturation magnetization and exchange stiffness material with high precision.