Scientific Highlights
Observation of a ubiquitous three-dimensional superconducting gap function in optimally doped Ba0.6K0.4Fe2As2
The iron-pnictide superconductors have a layered structureformed by stacks of FeAs planes from which the superconductivity originates. Given the multiband and quasi three-dimensional1 (3D) electronic structure of these high-temperature superconductors, knowledge of the quasi-3D superconducting (SC) gap is essential for understanding the superconducting mechanism.
Röntgenpreis for X-Ray research goes to Christian David
On 26th November 2010, Christian David, scientist at the Laboratory for Micro and Nanotechnology, received the Röntgenpreis for research in radiation science. David pioneered a method to enhance the quality of X-ray images. He received the award jointly with Franz Pfeiffer from Technische Universität München who worked closely together with him.
The award
Direct Determination of Large Spin-Torque Nonadiabaticity in Vortex Core Dynamics
We use a pump-probe photoemission electron microscopy technique to image the displacement of
vortex cores in Permalloy discs due to the spin-torque effect during current pulse injection. Exploiting the
distinctly different symmetries of the spin torques and the Oersted-field torque with respect to the vortex
spin structure we determine the torques unambiguously, and we quantify the amplitude of the strongly
Moving Monopoles Caught on Camera - researchers make visible the movement of monopoles in an assembly of nanomagnets
For decades, researchers have been searching for magnetic monopoles; isolated magnetic charges, which can move around freely in the same way as electrical charges – since magnetic poles normally only occur in pairs.
High-resolution method for computed nano-tomography developed
A novel nano-tomography method developed by a team of researchers from the Technische Universität München (TUM), the Paul Scherrer Institute (PSI) and the ETH Zurich opens the door to computed tomography examinations of minute structures at nanometer resolutions. The new method makes possible, for example, three-dimensional internal imaging of fragile bone structures. The first nano-CT images generated with this procedure was published in the renowned journal Nature on September 23, 2010.
Understanding plastic semiconductors better
New method allows important insights into polymer semiconductors
Semiconductors made from polymer materials are becoming increasingly important for the electronics industry – as a basis for transistors, solar cells or LEDs – showing important advantages when compared to conventional materials: they are lightweight, flexible and very cheap to produce.
New X-ray technique distinguishes between that which previously looked the same
A new method forms the basis for the widespread use of an X-ray technique which distinguishing types of tissue that normally appear the same in conventional X-ray images
The nature of nitrate at the ice surface
Trace contaminants such as strong acids have been suggested to affect the thickness of the quasi-liquid layer at the ice/air interface, which is at the heart of heterogeneous chemical reactions between snowpacks or cirrus clouds and the surrounding air. We used X-ray photoelectron spectroscopy (XPS) and electron yield near edge X-ray absorption fine structure (NEXAFS) spectroscopy at the Advanced Light Source (ALS) to probe the ice surface in the presence of HNO3 at 230 K.
The competition between organics and bromide at the aqueous solution – air interface as seen from ozone uptake kinetics and X-ray photoelectron spectroscopy
A more detailed understanding of the heterogeneous chemistry of halogenated species in the marine boundary layer is required. Here, we studied the reaction of ozone (O3) with NaBr solutions in presence and absence of citric acid (C6H8O7) under ambient conditions. Citric acid is used as a proxy for oxidized organic material present at the ocean surface or in sea spray aerosol.
Local current measurement in PEFC
Major barriers for a successful commercialization of Polymer Electrolyte Fuel Cells (PEFCs) are insufficient lifetime and high cost of platinum catalyst. A comprehensive understanding of aging and transport phenomena on all relevant length scales is a key to improve durability and to reduce precious metal loading. Flow fields as used in PEFCs for the distribution of the reactant gases over the electrode area cause inhomogeneities. The importance of down the channel inhomogeneities has been realized.