Show Main Menu Hide Main Menu

Information about the scientific lectures of the CUI Graduate Days 2015

Here you can find further information about the lectures of the CUI Graduate Days 2015 like abstracts and eventually the notes or slides of the lecturers.

Morning long scientific courses

Ultrafast phenomena in condensed matter systems: Prof. Thomas Elsaesser (Max-Born-Institute, Berlin, Germany)

This lecture combines an introduction in nonlinear light-matter interactions on ultrashort time scales with a discussion of recent results of ultrafast science. The following topics will be addressed:

–       Nonlinear resonant and nonresonant light-matter interactions

–       Generation of ultrashort pulses and experimental methods

–       Ultrafast processes in liquids and biomolecular systems

–       Nonlinear and quantum-coherent charge transport in solids in the terahertz frequency range

–       Ultrafast structural dynamics of solids mapped by time-resolved x-ray methods.

While theoretical aspects will be discussed, the lecture mainly focuses on experimental results.

Slides of lecture 1, lecture 2, lecture 3, lecture 4, lecture 5, and lecture 6.

 

Time resolved crystallography: Prof. Arwen Pearson (Universität Hamburg, Germany)

The timescales of interest in biomolecular science span a wide range, from  fast local reaction chemistry occurring on the femtosecond to nanosecond time scales, to the long range motions (changes in macromolecular conformation) over much slower timescales (tens of milliseconds to seconds). These often gate the reaction chemistry and link to biological responses such as signalling or complex assembly. Understanding biological mechanism thus requires understanding the coupling between structure, dynamics, chemistry and function over these time-scales as well as over a range of length scales from the molecular to the supramolecular and beyond. In this series of lectures we will look at the range of dynamic processes occuring in living organisms and discuss the biophysical tools that can be used to probe these, illustrated with a series of case studies. We will also discuss the peculiar challenges that arise in the application of physical and chemical anaytical tools to the study of biological soft matter.

 

Soft matter and glass physics: Prof. Walter Kob (University of Montpellier, France)

Soft matter refers to materials that are easily deformable at ambient temperatures since the interaction strength between the constituent particles are comparable with the thermal energy scale. Important examples are colloids, polymers, foams, gels, liquids crystals, as well as many biological systems, i.e. materials that are ubiquitous in our daily life (plastics, cosmetics, food, etc.). Since the particles of most soft materials have a non-trivial shape (polymers) or are not of strictly identical size (colloids), the material they form is usually not crystalline but amorphous, i.e. a glass. In order to understand these materials it is therefore necessary to understand the properties of viscous liquids and glassy materials, systems that from the point of view of theory are rather difficult to handle.

In these lectures I will first give an introduction to the physics of soft matter and how their properties can be characterized on the microscopic as well as the macroscopic level. I then will present the theoretical approaches that are used to describe these complex materials. Subsequently I will discuss the phenomenon of the glass transition and how it relates to the properties of soft materials as well as other type of glasses.

Slides of lecture 1, lecture 2, lecture 3, and lecture 4.

 

Afternoon short scientific courses

Strongly correlated systems in condensed matter and ultracold atoms: Prof. Rosario Fazio (Scuola Normale Superiore di Pisa, Italy)

1) Phase diagram(s) of interacting bosons on a lattice
2) Non-equilibrium properties – adiabatic dynamics
3) Quantum quenches

In the first lecture I will introduce the basic models of strongly interacting systems on a lattice, I will discuss how they can be realised in optical lattice and (in the case of bosonic systems) their equilibrium phase diagram. In the second and third lectures I will move to non-equilibrium. In the second lecture I will discuss the so called Kibble-Zurek mechanism when a system is dragged adiabatically through a critical point. I will conclude the third lecture by discussing how/when a system thermalises after a quantum quench.

Slides of the lecture

 

Electron microscopy: Dr. Rudolph Reimer (Heinrich Pette Institute, Hamburg, Germany)

Electron microscopy (EM) is currently undergoing a revival. Recent developments in the fields of cryo EM and volume EM help to circumvent the obstacles of classical electron microscopy and open a complete new view on many current research topics. The lecture will give an overview over the principles and historical developments in electron microscopy, the main problems of classical EM and modern solutions to them. Cryo-techniques and 3D EM will be discussed in detail. A strong focus will be put on the preparation of biological samples, with intent to keep them in a “lifelike” state. All topics will be illustrated with examples from recent research projects.

Slides of lecture 1, lecture 2, lecture 3, and lecture 4.

 

Ultrafast dynamics in nano-magnetic systems: Prof. Ralf Röhlsberger (Desy, Hamburg, Germany)

The manipulation of magnetic moments on nanoscale dimensions and ultrashort timescales has developed into a fascinating research topic in modern magnetism, not only due to its technological relevance for magnetic data storage and retrieval, but also for the understanding of the underlying principles of magnetization dynamics. This field is of particular importance nowadays when it comes to replace the electric charge by the magnetic spin as elementary carrier for information which could form the basis for a spin-based information technology of the future.

Time scales in magnetism reach from geological periods of the Earth’s magnetic field reversal down to the femtosecond regime that is related to the exchange interaction between individual magnetic spins. The quest for increasingly faster speeds of information processing in magnetic media together with the intrinsic limitations that are connected with the generation of magnetic field pulses by electric currents have initiated intense searches for ways to control magnetization by other means than magnetic fields. Here the interaction of ultrashort pulses of light with magnetic materials is of paramount importance.

From the discovery of subpicosecond demagnetization over a decade ago to the recent demonstration of magnetization reversal by femtosecond laser pulses, the manipulation of magnetic order by ultrashort pulses of light has become a fundamentally challenging topic with a potentially high impact for future spintronics, data storage and manipulation, and quantum computation. Understanding the underlying mechanisms implies understanding the interaction of photons with charge-, spin-, and lattice degrees of freedom, as well as the exchange of angular momentum between them.

This lecture series will review the manipulation and investigation of magnetic order by electromagnetic waves in a systematic way, ranging from microwaves all the way up to hard x-rays as they are generated by synchrotron radiation sources and x-ray lasers.