Available Student Projects
We mainly have experimental activities i.e. offer a variety of measurements addressing materials properties (see our research pages for an overview). There are also a number of possible tasks involving numerical simulations (e.g. light scattering or micromagnetic), or improving control programs for experimental setups.
The effect of geometric imperfections on magnetic properties
How does internal and external geometric imperfections, i.e. voids and surface roughness, influence the magnetic and electric properties of bulk materials on a macroscopic scale? Computational models, i.e. finite element models, of bulk materials are commonly set up with perfect geometry/mesh and homogeneous material properties. The material properties used, such as the hysteresis loop, are extracted from carefully controlled "perfect" specimens and do not perfectly map to the bulk materials. The aim of this project is to quantify this mapping in relation to for example void distributions and surface roughness and to generalise the effects of imperfections on resulting magnetic properties.
Mattias Unosson for information on methods
Björgvin Hjörvarsson on other matters
Simulation and fitting of polarised neutron reflectivity data
The task within this project will be to simulate and fit polarised neutron reflectivity data from EuS/TM multilayers. Recently, strong room temperature magnetisation was observed in EuS/Co multilayers. In a series of neutron scattering experiments we have collected data than can be used to estimate experimentally the extension of the magnetic polarisation in EuS. You will use a specifically developed fitting tool for reflectivity data, called GenX. Resulting data will be combined with input from x-ray circular magnetic dichroism experiments in order to provide more reliable information. This project requires some basic knowledge about computer use and optionally programming.
Magnetotransport in amorphous nanoscale films and multilayers
Developing materials and devices where the magnetic and electrical properties are linked is the subject of the relatively new field of spintronics. This project involves studying the electrical transport properties of amorphous magnetic films. Amorphous magnetic films are attractive for spintronic devices due to their high degree of uniformity and potential for tuning of magnetic and electronic properties. Yet, the mechanisms defining their electrical properties are not well understood. The project will involve measurements of resistivity, Hall effect and magnetoresistance in nanoscale films from 10 K up to room temperature. Multilayers of alternating magnetic and non-magnetic layers will also be studied.
X-ray reflection studies of lyotropic liquid crystals
Concentrated solutions of some surfactants in water form liquid crystal phases. There is evidence that some of these will order against planar substrates. The project will involve design of a cell to allow X-ray measurements under controlled atmospheres on an X-ray reflectometer/diffractometer.
Magneto-optic spectroscopy of advanced materials
This project is focused on the exploration of energy dependent rotation of light from surfaces. The aim is twofold: Establish spectroscopic magneto optical of few elements and secondly to explore how thick a layer has to be to give the signature corresponding to the bulk like response.
Liquid particle dynamics
The project work is aimed at understanding how to make novel liquid conductors that are formed of dispersions of particles in liquids. The initial study will will investigate the flow properties (rheology) of particles in oils and how flow and other applied fields alter the structure. Experiments will involve studies with optical microscopes and light scattering. The project will require design of appropriate measuring cells and use of computers to analyse images. Extension of an existing light scattering apparatus with a CCD camera will be useful for studying anisotropic scattering.
Surface ordering under shear
In fluid mechanics flow is described by the Navier-Stokes equation in the bulk and a no-slip boundary condition at the solid interface. However, recently, both experiments and theory have shown that on a microscopic scale liquids may undergo significant slip at a solid wall. The magnitude of the slip length and its relation with the relevant surface parameters on which it depends, are presently under intense discussion in the literature and not well understood on the nm length scale. We contribute to this issue by investigation of surface ordering in samples that show correlations on mesoscopic length scales as well as Newtonian liquids mainly by scattering techniques.
Characterization of functionalized surfaces
Surface coatings are of eminent importance for application as well as for fundamental science. One possibility to functionalize surfaces is to cover them with molecules that change the surface energy. Typically the quality and properties of the coating has then to be verified by x-ray reflectometry, ellipsometry and contact angle measurements. This project will involve the development of these techniques and apply them to kinds of surface coatings.
Magneto-plasmonics - Understanding the correlation between plasmons and magneto-optics
Plasmons are collective electronic resonances that have a huge impact on the optical properties of metallic materials and nanostructures. With optical diffractometry and ellipsometry in combination with measurements of the magneto-optical effects one has access to all optical properties of a material. With the advent of plasmonics and metamaterials one has the possibility to tune those properties by using nanostructures to control the reflectivity of the material or even the the properties of the emitted light itself. This project will involve magnetic nanostructures and optical and magneto-optical measurements for characterization of magneto-plasmons.
On this page we only show a few examples. If you are interested in a visit and further discussions about ongoing and planned projects, please contact one of these people:
- Björgvin Hjörvarsson (overall responsible for the division's research program)
- Adrian Rennie (e.g. soft matter and neutron scattering)
- Gabriella Andersson (e.g. magnetic materials, domain imaging)
- Vassilios Kapaklis (e.g. magnetic materials, optics, x-ray scattering)
- Max Wolff (e.g. hydrogen in metals, solid-liquid interfaces, neutron scattering).