SwissFEL

The latest large research facility at PSI generates very short pulses of X-ray light with laser-like properties. This enables researchers to observe extremely fast processes, such as how new molecules are created in a chemical reaction; to determine the detailed structure of vital proteins; or to determine the relationship between electronic and atomic structure in materials. This new knowledge expands our understanding of nature and leads to many practical applications, for instance new pharmaceuticals, more efficient processes in the chemical industry, or new materials for electronics.

Read more at: SwissFEL
A schematic of the setup employed for the experimental demonstration. X rays are focused and scatter off a test sample that can be displaced laterally with nanometer precision. The diffraction pattern produced by the scattered X rays is collected by a detector. The sample is reconstructed on a computer from the diffraction data (see other images).

Imaging fluctuations with X-ray microscopy

X-rays allow an inside look at structures that cannot be imaged using visible light. They are used to investigate nanoscale structures of objects as varied as single cells or magnetic storage media. Yet, high-resolution images impose extreme constraints on both the X ray microscope and the samples under investigation.

A scheme showing the LIFT process. The laser beam punching out an Alq3 pixel for transfer from the donor to the receiver substrate is shown in (a), and pair of electroluminescent pixels are shown with a bias applied in(b).

The fabrication of small molecule organic light-emitting diode pixels by laser-induced forward transfer

Laser-induced forward transfer (LIFT) is a versatile organic light-emitting diode (OLED) pixel deposition process, but has hitherto been applied exclusively to polymeric materials. Here, a modified LIFT process has been used to fabricate small molecule Alq3 organic light-emitting diodes (SMOLEDs). Small molecule thin films are considerably more mechanically brittle than polymeric thin films, which posed significant challenges for LIFT of these materials.

Magnetic nano-chessboard. Upper part: Visualisation of the molecule using a scanning tunnel microscope; the molecular structure is indicated for two of the molecules. Lower part: Schematic representation of the self-assembly of the molecules; they fit together like pieces of a jigsaw puzzle and arrange themselves in a continuously alternating pattern.

Magnetic nano-chessboard puts itself together

Researchers from the Paul Scherrer Institute and the Indian Institute of Science Education and Research (Pune, India) have managed to ‘turn off’ the magnetization of every second molecule in an array of magnetized molecules and thereby create a ‘magnetic chessboard’. The magnetic molecules were so constructed that they were able to find their places in the nano-chessboard by themselves.

Spin ladders and quantum simulators for Tomonaga-Luttinger liquids

Magnetic insulators have proven to be usable as quantum simulators for itinerant interacting quantum systems. In particular the compound (C5H12N)2CuBr4 (for short: (Hpip)2CuBr4) was shown to be a remarkable realization of a Tomonaga-Luttinger liquid (TLL) and allowed us to quantitatively test the TLL theory.

Persistent Spin Dynamics Intrinsic to Amplitude-Modulated Long-Range Magnetic Order

In geometrically and/or exchange frustrated materials spin fluctuations may endure down to lowest accessible temperatures - the phenomenon known as persistent spin dynamics. Since spin fluctuations hinder the onset of extended static correlations, persistent spin dynamics and long-range magnetic order are generally considered as mutually exclusive. Remarkably, their coexistence has been found in several frustrated magnetic systems but was lacking a suitable explanation.

Electric field control of the skyrmion lattice in Cu2OSeO3

Skyrmions are topologically protected magnetic spin 'whirls' that form a hexagonal 2D lattice in non-centrosymmetric magnets. Until recently, skyrmions had only been observed in itinerant metallic alloys such as MnSi, where they can also be manipulated by applied electric currents.

Example of skeletonization techniques used to measure bubble and pore throat sizes. a) The topology preserving skeleton with nodes shown in red at the intersections of the branches.  b) The maximal inscribed spheres used to calculate the bubble volumes. c) The maximal inscribed spheres used to calculate the pore throat diameters.  Wall thicknesses were also determined using maximal inscribed spheres. (Graphic: J. Fife/PSI; D. Baker/McGill University)Please note: all images are for single use only to illust…

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.