Scientific Highlights
X-rays provide insights into volcanic processes
Experiments performed at the Paul Scherrer Institute (PSI) investigate processes inside volcanic materials that determine whether a volcano will erupt violently or mildly.
New Insights into Superconducting Materials
An American-Swiss research team has used a new X-ray technique at Swiss Light Source (SLS) of the Paul Scherrer Institute (PSI) to investigate the magnetic properties of atomically thin layers of a parent compound of a high-temperature superconductor. It turns out that the magnetic properties of such thin films differ by only a surprisingly small degree from those of macroscopically thick samples.
Power-Law Spin Correlations in the Pyrochlore Antiferromagnet Tb2Ti2O7
Spin correlations with power-law decay are usually associated with a critical point, but stable phases with power-law correlations may exist in frustrated magnets. Such phases are interesting, because they represent model materials where short-range interactions and local constraints lead to emergent symmetries and fractional quasiparticles.
ERC Grant for the development of a new imaging method with high potential clinical impact
Marco Stampanoni, Assistant Professor for X-ray microscopy at the ETH Zürich and Head of the 'X-ray Tomography Group' of the SLS has been recently awarded one of the coveted European Research Council (ERC) Starting Grant for the project PhaseX: 'Phase contrast X-ray imaging for medicine'. Marco Stampanoni's project will be supported by the ERC with 1.5 million euros for the next 5 years. The highly competitive ERC Starting Grants are reserved for outstanding young research talents.
Two types of adjacent dimer layers in the low temperature phase of BaCuSi2O6
The interest in BaCuSi2O6 is motivated by its extraordinary phase diagram with field-induced Bose-Einstein condensation. Being a quantum paramagnet at zero magnetic field down to the lowest temperatures, the system displays a quantum phase transition into a magnetically ordered state at the critical value of magnetic field of ~23.5 T.
Three-Dimensional Electron Realm in Crystalline Solids Revealed with Soft-X-Rays
The electronic band structure E(k) as energy E of the electrons depending on its wavevector k is the cornerstone concept of the quantum solid state theory. The main experimental method to investigate E(k) is the angle-resolved photoelectron spectroscopy (ARPES). However, a small photoelectron escape depth of a few Å largely restricts the applications of ARPES to two-dimensonal crystals.
Laser-Induced Forward Transfer for the Fabrication of Devices
In conjunction with the increasing availability of cost-efficient laser units during the recent years, laser-based micromachining techniques have been developed as an indispensable industrial instrument of ‘‘tool-free’’ high-precision manufacturing techniques for the production of miniaturized devices made of nearly every type of materials. Laser cutting and drilling, as well as surface etching, have grown meanwhile to mature standard methods in laser micromachining applications where a well-defined laser beam is used to remove material by laser ablation. As an accurately triggerable nonmechanical tool, the ablating laser beam directly allows a subtractive direct-write engraving of precise microscopic structure patterns on surfaces, such as microchannels, grooves, and well arrays, as well as for security features. Therefore, laser direct-write (LDW) techniques imply originally a controlled material ablation to create a patterned surface with spatially resolved three-dimensional structures, and gained importance as an alternative to complementary photolithographic wet-etch processes. However, with more extended setups, LDW techniques can also be utilized to deposit laterally resolved micropatterns on surfaces, which allows, in a general sense, for the laser-assisted ‘‘printing’’ of materials.
Supported gold as catalyst for the decomposition of ammonia precursors in the selective catalytic reduction of NOx
Titanium dioxide-supported gold was found to catalyze the hydrolysis of formate-based ammonia precursor compounds which are proposed for the selective catalytic reduction of nitrogen oxides (NOx) in combustion exhaust gas. In contrast to other noble metals, the supported gold does not oxidize the released NH3, while it maintains decomposition of intermediate formic acid.
Supported gold as catalyst for the decomposition of ammonia precursors in the selective catalytic reduction of NOx
Titaniumdioxide supported gold was found to catalyze the hydrolysis of formate-based ammonia precursor compounds which are proposed for the selective catalytic reduction of nitrogen oxides (NOx) in combustion exhaust gas. In contrast to other noble metals, the supported gold does not oxidize the released NH3, while it maintains decomposition of intermediate formic acid.
Ultra-short X-ray laser pulses precisely surveyed for the first time
X-ray lasers belong to a modern generation of light sources from which scientists in widely different disciplines expect to obtain new knowledge about the structure and function of materials at the atomic level. On the basis of this new knowledge, it could then be possible one day to develop better medicines, more powerful computers or more efficient catalysts for energy transformation.