Prof.
Björgvin Hjörvarsson
(Uppsala University)
15/02/2010, 11:00
Give a thorough description of the experimental results
concerning dimensionally confined magnetic systems.
Dr
Elena Vedmedenko
(University of Hamburg)
15/02/2010, 14:00
The correlation function is an essential ingredient of any
theory of phase transitions, covering electronic systems,
liquids or magnets, since it provides direct information on
critical properties of a system. With the Ornstein-Zernike
law its general analytical form is known for infinite
systems at infinite observation times, above the critical
temperature.
However, important...
Dr
Anders Bergman
(Uppsala University)
16/02/2010, 10:00
We study the Fe/W(110) monolayer system through a
combination of first principles calculations and atomistic
spin dynamics simulations. We focus on the dispersion of
the spin waves parallel to the [001] direction. Our
results compare favorably with the experimental data of
Prokop et al. [Phys. Rev. Lett. 102, 177206], and
correctly capture a drastic softening of the magnon...
Prof.
Peter Holdsworth
(Ecole Normale Supérieure de Lyon)
16/02/2010, 13:00
Dr
Holger Meyerheim
(Max-Planck-Institut für Mikrostrukturphysik, Halle, Germany)
17/02/2010, 11:00
The talk reviews recent studies on the geometric
structure of oxide films in the ultra thin film limit and their
implications on their magnetic (multiferroic) properties. In
a first example the structural phase transition in pure
and Cobalt-doped ZnO-film is discussed. Depending on
film thickness a transition from the bulk Wurtzite (WZ)-
type structure to the...
Prof.
Steve Bramwell
(University College London)
17/02/2010, 14:00
Dr
Simon Banks
(University College London)
18/02/2010, 10:00
Recent neutron scattering experiments [1] have
sharpened the picture of an algebraic spin liquid phase
in CsNiCrF6, originally proposed by Zinkin et al. [2].
Anderson famously predicted that systems such as this,
with equal numbers of two magnetic species populating
a pyrochlore lattice, should favour configurations with
two of each type of ion present on every...
Prof.
Mats Wallin
(Theoretical Physics KTH)
18/02/2010, 11:00
Disordered systems often display new emergent phases
and phase transition, for example, spin glasses and similar
states in quantum fluids with disorder. Other examples
where confinement effects play an important role are given
by porous matter. Experiments on such systems often
indicate strong finite size effects that need to be
understood. We use an approach involving Monte Carlo...
Prof.
Patrik Henelius
(KTH Royal Institute of Technology)
18/02/2010, 14:00
Due to the long range and angular dependence of the
dipolar interaction sample shape plays a crucial role in
determining the ordered state of magnetic materials where
long-range interactions are important. This should also
apply to magnetic mulitlayer systems and I propose
studying the effects of the often neglected dipolar
interaction in these novel materials.
Prof.
Peter Holdsworth
(Ecole Normale Supérieure de Lyon)
19/02/2010, 10:15
Dr
Simon Banks
(University College London)
22/02/2010, 13:15
It is well known that the order parameter for the 2dXY
model is zero in the thermodynamic limit, yet it remains
measurable even for macroscopic systems. Thus our
ability to observe the KT transition via changes in the
magnetization is a result of the "confinement" of the
system to finite size. We have been working on a family
of related models in one and three-dimensions...
Dr
Per Håkan Lundow
(KTH Royal Institute of Technology)
22/02/2010, 14:15
Prof.
Hannes Jonsson
(University of Iceland)
23/02/2010, 10:15
Prof.
Robin Stinchcombe
(University of Oxford)
24/02/2010, 10:15
Prof.
Olle Eriksson
(Uppsala University)
24/02/2010, 13:15
In the talk I will review some recent results on first
principles theory of magnetism and magnetic materials.
In particular, results of giant magnetic anisotropies will
be described, and I will put some emphasis on
technological aspects of this property. I will also describe
recent developments in theory of spin-dynamics and
how this reproduces observations on thin-film...
Dr
Lars Nordström
(Uppsala University)
24/02/2010, 14:15
In most magnetic phase transitions the focus is on the
lowest multipole, the dipole which is directly related to
the magnetic moment. We will in this work argue that in
some cases higher order multipoles are driving the
transition and the dipole is a secondary effect.
The concept of spherical tensors or multipoles of an
open atomic shell is first reviewed and discussed.Some
of...
Andrea Taroni
(Uppsala University)
25/02/2010, 10:15
The properties of ultrathin magnetic structures are
influenced by many length scales that reflect both
generic physics and chemical detail. A striking example is
the experimentally determined shift of the critical
temperature as a function of film thickness. While all
systems experience a pronounced suppression in Tc with
decreasing film thickness, the magnitude of this shift...
Dr
Tom Hase
(University of Warwick)
26/02/2010, 10:15
Prof.
Björgvin Hjörvarsson
(Uppsala University)
26/02/2010, 11:15
