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Magnetic Materials - Prof. J. M. Cadogan - Tier I CRC
We use nuclear techniques (Neutron Diffraction, Mössbauer Spectroscopy and pulsed NMR) and atomic techniques (Magnetometry, thermal analysis, x-ray diffraction) to investigate the intrinsic magnetic structures formed by a variety of materials, with a particular emphasis on intermetallic compounds comprising the Rare-Earth and Transition elements. Such materials are of interest from both fundamental and applied points of view. They provide us with the opportunity to study the interplay of localized 4f electrons with de-localised 3d electrons and we model the intrinsic magnetism of these compounds in terms of the fundamental magnetic exchange and crystal field interactions. From the practical point of view, they provide the world’s strongest permanent magnets and the next generation of refrigeration materials. In addition to these crystalline compounds, we also investigate amorphous and nanocrystalline materials and meteorites.
Dynamic Spintronics - Prof. C.-M. Hu
The Dynamic Spintronics Group originated at the University of Hamburg, Germany, and moved to the University of Manitoba at the end of 2005. The Dynamic Spintronics Group conducts experiments investigating magnetism, spintronics, and metamaterials, in close collaboration with faculty in the Department of Electrical and Computer Engineering. The research focus in on the interplay between spins, charges, and photons in low-dimensional systems. Current projects include:
   - spin and magnetization dynamics in micro/nano-structured ferromagnetic metals
   - spin and charge properties in ferromagnetic semiconductors
   - high frequency wave physics in spintronic and metamaterials
The research in these directions is motivated by the rapid advances in information and communication technologies and the exciting progress in the new discipline of spintronics, as highlighted by the 2007 Nobel Prize in Physics awarded to Albert Fert and Peter Grünberg "...for the discovery of Giant Magnetoresistance".
Nanomagnetism - Associate Prof. J. van Lierop
The research plan of the Nanomagnetism Research Group is composed to two basic thrust areas. One is to understand the surface, core and interaction properties of magnetic nanoparticles. That is, magnetic metals and oxides with sizes 1-100 x 10-9 m that have approximately 1020 fewer atoms then the average bulk magnetic sample. Finite-size effects rule at these length scales. The second thrust area is to use nanoparticle assemblies in amorphous and precisely ordered three dimensional lattice forms to design systems that exhibit a collective state transition that would mark a fundamentally new regime with nanoparticle properties no longer relevant to a thermally activated process. Central to both of these research thrusts is nanoparticle sample synthesis and characterization.
Nanoscale Physics - Prof. T. Chakraborty
Despite a span of more than two decades since the discovery of this effect, with a truly large number of people from various sub-fields doing intensive research, and after two Nobel prizes, the quantum Hall effects (QHE) still remain a major topic of interest in condensed matter physics. Electrons moving on a plane at extremely low temperatures and under the influence of a strong perpendicular magnetic field are known to exhibit very curious behavior. The most famous one is the fractional quantum Hall effect at 1/3 filled lowest Landau level discovered by A.C. Gossard, H. Stormer, and D. Tsui in 1982. The theory of Robert Laughlin described in 1983 the "1/3-state" where electrons condense into a ground state which is a charge-neutral liquid. The low-lying excitations in the liquid behave like particles that carry fractions (e/3 for the 1/3 state) of electron charge. The liquid in this state is famously known to be incompressible . Stormer, Tsui and Laughlin shared the Nobel prize in 1998 for initiating a revolution that is yet to subside. As a result of intense investigations of the quantum Hall effect over the past two decades, a lot is known theoretically about the 1/3 state, but very little in terms of direct information of the electronic properties of the incompressible state.
Hysteresis in Magnetic Materials - Prof. R. M. Roshko
Hysteresis is one of the most widely recognized signatures of magnetically ordered materials. It is a nonequilibrium, history dependent phenomenon, which ultimately originates from metastability, that is, the existence of very many local minima in the free energy landscape in configuration space. It is also a property of considerable interest from a technological perspective, since virtually all applications of magnetism exploit hysteresis in some way. In broad terms, the goal of the current research is to measure the field and temperature dependence of the irreversible response of a wide spectrum of magnetic materials, including canonical ferromagnets, sintered permanent magnetic, frustrated spin glasses, and froze suspensions of nanodimensional particles, and to interpret these data withing the framework of a model which decomposed the free energy into an ensemble of interacting, temperature dependent, two-level subsystems.
Novel Magnetic Materials - Prof. G. Williams
The general objectives of our research program are to elucidate connections between the magnetic and transport properties of materials. The experimental techniques that are employed include both novel field and temperature dependent acsusceptibility and spontaneous resistive anisotropy techniques developed by our group as well as more conventional magnetic and transport measurements. These measurements are often supplemented by model/numerical calculations. Current research activities focus on transition metal compounds, specifically, manganese perovskites which exhibit so-called collosal magnetoresistance (CMR) - a very large change in resistance with applied magnetic field, and shape-memory alloys such as Ni-Mn-Ga which have been found to display a giant magnetocaloric effect (GMCE), a large temperature change when a magnetic field is applied. Understanding the behaviour of CMR systems has been identified as one of the more significant challenges currently facing the Materials Science community.

From an applied perspective, both classes of materials appear to have practical applications. The former as field sensors, in particular as read-write heads in magnetic storage systems, as fuel cells, and for fabricating devices based on spin rather than charge transport. GMCE materials, following the Kyoto protocol, are also the subject of much recent interest for use in "magnetic" refrigeration.
Cooperative Phenomena in Disordered Systems -
Prof. B. Southern
Most of the knowledge about phase transitions that has been obtained from statistical mechanics concerns perfectly translationally invariant systems. This success in understanding the collective behavior of conventional materials has led to an increased interest in systems that exhibit a novel type of ordering as a consequence of competing interactions or "frustration". In particular, geometrically frustrated systems (having as a basic building block triangles of antiferromagnetic bonds) have been and are still the object of extensive experimental and theoretical studies. The phenomenon of frustration arises in magnetic systems when there is no unique direction for a spin to choose to minimize its energy, leading to non trivial and often multiple ground states. As a consequence of frustration, spectacular and often unexpected behaviour is encountered at low temperatures due to the high degeneracy of the ground state. These systems often exhibit a glassy behaviour. Intriguing experimental results find that a large portion of the materials studied show a magnetic spin-freezing transition similar to what is found in highly disordered magnetic materials called spin glasses. The origin of this spin freezing constitutes a major puzzle in this field.

In the last few years off-equilibrium approaches have been successfully used to describe systems which show a very slow dynamics, such as spin glasses and structural glasses. Aging effects, such as a history dependence in the time evolution of correlation and response functions after the system has been quenched into some non-equilibrium state, appear in a variety of ordered and disordered systems which are essentially out of equilibrium on experimental time scales. The modeling of these systems requires intensive computational effort using parallel machines. The results of these studies should enhance our basic understanding of frustrated antiferromagnets in order to interpret available experimental results.