Finished Projects

The existence of polar, i.e. ferromagnetic or ferroelectric ordering, in dipolar liquids has been a long-standing open question. Some of the models predicted it some not. The main issue is that appropriate nearest neighbours’ positional and orientational correlations are crucial for the appearance of the polar phase and are difficult to predict correctly. Recently, it has been shown that in a special kind of ferrofluids, made of magnetic nanoplatelets suspended in alcohols above a certain volume fraction a ferromagnetic nematic phase appears. These ferrofluids are therefore liquid magnets and they are sensitive to very small magnetic fields. They present a unique model system, in which positional and magnetic correlations between the constituents can be studied, which are crucial for the existence of the ferromagnetic phase. The aim of this proposal is to join the expertise of the Slovenian research group at Institut Jozef Stefan in design and properties of liquid magnets with that of the Austrian research group at University of Vienna, Faculty of Physics on using SAXS and SANS for studies of the microstructure of materials.

• ASSIC Austrian Smart Systems Integration Research Center

Scientific Aims:

The research activities of ASSIC Austrian Smart Systems Integration Research Center focus on intelligent system integration based on micro- and nanotechnologies. With its research activities, ASSIC offers sound system knowledge about components, technologies, materials, assembly and interconnection technologies.

ASSIC focuses on three research areas:

Microsystem Technologies: with a focus on the development of acoustic and magnetic micro components and technologies as well as on the associated manufacturing processes.

Heterogeneous Integration Technologies: comprises the research of functional packaging, assembly and interconnection technologies for micro-electro-mechanical system components, trendsetting thin-film packaging technologies and the integration of subsystems at chip level in micro modules.

Smart Systems Solutions: for the integration of functional modules into innovative photonic measurement systems, as well as for the development of necessary design methods and technologies.

Scientific Aims:

Within the research proposal various media design will be investigated concerning the potential for BPM and granular recording using heat assisted recording. The potential of shingled magnetic recording and center recording will be investigated. Furthermore pulsed magnetic recording, where the laser pulse is applied only for 100 ps or shorter is compared with continuous laser heating, where the laser power is switched on constantly.

• Frauscher

Scientific Aims:

Within this project, inductive railway sensors are investigated and optimized that are used to run, monitor and protect  operational reailway network. 

• Huawei RDA

Scientific Aims:

This project aims to investigate and optimize two dominant loss mechanisms in soft magnetic composites (SMC), namely hysteresis losses and eddy-currents losses. Advanced multiscale simulation techniques will be developed and applied in order to understand the influence of material parameters and geometry on these loss mechanism. This will enable the optimization of the granular core materials for MHz power applications.

• Infineon AG
• Magnetfabrik Bonn
• Donauuniversität Krems

Scientific Aims:

Within this project we aim to apply advanced simulation techniques for the development and design of new sensor devices for the automotive industry, which are also applicable for bio application. This project which involves world renowned experts in micromagnetics and Infineon, the world market leader in semiconductor based sensors will lead to the unique opportunity to solve the challenging problem of computer aided design and development of large scale semiconductor-based magnetic sensors.

The applicant’s micromagnetic simulation software FEMME is used by major companies worldwide for the optimization of giant magnetoresistance (GMR) and tunnel magnetoresistance (TMR) read heads in hard disc drive systems. The application of this software tool for the design of magnetic sensors for automotive industry and bio application is far from obvious and it is a very challenging task. The challenge is that the involved lateral dimensions in this new application area are at least by a factor 10 larger. This increases the number of unknowns for 3D simulation by a factor of 1000. Hence, innovative and new modeling concepts have to be developed in order to succeed with this task.

The work of this proposal brings together Austrian expert groups which are world leaders in their field. This interplay between simulation and experiments is believed to be the key success factor of this project. This combined effort will be used to optimize existing sensors, to solve performance issues, and to develop new designs for improved sensing.

• BOGEN Electronic GmbH, Germany
• INESC Microsystems and Microtechnology, Portugal

Scientific Aims:

• to bring a new magnetic measurement solution with high accuracy
• to improve BOGEN’s position in the magnetic measurement market
• to increase the turnover and create new jobs

• Investigate symmetry of domain twins, related symmetry allowed displacements and corresponding order parameter couplings to calculate profiles and functional properties within domain walls of finite thickness.
• Study the role of functional domain walls on the macroscopic properties of materials. What is the role of domain miniaturisation on superior materials properties?
• Investigate dynamics of domain walls to shed light onto the question: “Is domain freezing a glass transition?” Can it be described in the frame of glass – theory?

• Irena Drevensek-Olenik, University of Ljubljana
• Jozef Stefan Institut, Ljubljana, Slovenia

Scientific Aims:

Neutron interferometry with three perfect-crystal slabs in Laue geometry (triple-Laue, or LLL) is a tool especially suited for investigation of fundamental physics questions. Unfortunately, with its thick-crystal components, at least half of the intensity is lost at the second slab because the diffrac­tion efficiency (reflectivity) is rapidly oscillating as a function of angle of incidence. Thus, in most cases, only an averaged, smeared-out rocking curve (reflectivity vs incident angle) can be ob­served with a realistic beam divergence. A possible workaround to this intrinsic intensity-loss prob­lem could be to employ Bragg-geometry for some or all of the interferometer components. Instead of LLL-, one could construct LBL (Laue-Bragg-Laue) interferometers. The Bragg-geometry's major advantage is that its reflectivity shows a so-called Darwin-plateau: The reflectivity might reach unity and be constant in a relatively wide neighborhood of the Bragg angle. 

In recent years, we have put forward nanocomposite materials as complementary approach to de­velop neutron-optical devices for cold and very cold neutrons. The proposed project is dedicated to proof-of-principle experiments to show that artificial, non-crystalline grating structures -- optically recorded in nanocomposite materials -- can work in Bragg-geometry for neutron diffraction.

Heat-assisted recording (HAMR) combined with bit-patterned media (BPM) is one of the candidate technologies to overcome present limits in magnetic recording and to possibly extend magnetic recording to storage densities of several tens of Tb/in2. BMP are required to reduce the transition jitter noise that would be present in granular recording media, where the bit transitions are invariably irregular given that each bit requires about 30 irregular magnetic grains of the recording media. To ensure stability of the magnetic information over time, high anisotropy is engineered, which gives rise to a large coercivity. In turn heat assistance is necessary to raise the temperature during writing thereby reducing the medium coercivity to levels that can be written. However, elevated temperatures also lower the magnetization which substantially increases thermally induced recording errors. One of the co-applicants (D. Suess) has proposed a composite media structure, consisting of two exchange-coupled layers with different Curie temperatures, to overcome the above limitations.

The goal of the project addresses a novel exchange-coupled composite Curie temperature modulated bilayer system for HAMR/BPM. Unique experimental methods are available in the two experimental groups with a thorough background in magnetic thin film research. The experimental work will be supported by a theory group having a long-standing experience in the field of magnetic recording systems.

• Prof. Dirk Praetorius, Institute for Analysis and Scientific Computing
• Dr. Thomas Schrefl, Donauuniversität Krems

The main objectives of the project is to develop mathematically reliable, numerically stable, and computationally effective FEM integrators for the simulation of thermally driven magnetization dynamics at the mesoscale. This includes to implement a FEM integrator for thermally driven magnetization dynamics for production runs on massively parallel hardware architectures. The achieved results and derived implementations will be validated with real-life data provided by, Seagate Technology. With the techniques and developed simulation tools, we will provide computational guidelines for the design of composite magnetic structures for future ultra-high storage devices.

• Martin Copic, Jozef Stefan Institut, Ljubljana, Slovenia

Scientific Aims:

We aim at demonstrating that polymer structures can be loaded with ferromagnetic/superparamagnetic NP species to obtain optical elements that work as polarizing beamsplitter for CN and VCN instrumentation. Nanotechnology, i.e. methods associated with this term, has become standard lab-technology. Surprisingly, it has found little appreciation in neutron optics. We intend to take advantage of the many interesting features of nanocomposite materials and apply them to the field of neutron optics. We emphasize the prospects of our ideas for neutron scattering instruments relying on cold neutrons. A business-card-size polarizing beamsplitter implemented in a small electromagnet can easily be included in the set-up of existing SANS instruments. Such an add-on would promptly expand the applicability of instruments so far not equipped with polarized-neutron options to a much wider range of scientific questions.