Scientific Highlights

The editors of Applied Physics Letters (APL) named Dr. Soichiro Tsujino, head of the XFEL nanoengineering group of LMN, as one of the 16  ALP top reviewers in 2018.

While information technology over the last 50 years has been based on conventional semiconductor electronics, future technologies – aiming to enhance the performance of computers, sensors and to secure data communication for the future internet – will use the quantum origins of nature.

This symposium highlighted the opportunities for the traditional semiconductor materials to remain the platform on which also the new quantum technologies will build on. The symposium, in part a celebration of the career of PSI Quantum Technologies group leader Hans Sigg, was held at ETHZ and included notable speakers both local and international, Gabriel Aeppli (PSI, ETHZ & EPFL), Jérôme Faist & Klaus Ensslin (ETHZ), Theo Rasing (RU Nijmegen), Giordano Scappucci (QuTech-TU Delft) and Klaus von Klitzing (MPI Stuttgart).

In a collaboration within the network of the Swiss Nanoscience Institute, the formation of free-standing molecular monolayers using self-assembly processes has been demonstrated. The results of the study have been published in the February 2019 issue of Science Advances.

Dr. Yasin Ekinci, Head of the Advanced Lithography and Metrology Group and ad interim Head of the Laboratory for Micro and Nanotechnology, has been elected to the grade of Fellow of The International Society for Optics and Photonics (SPIE).

The research group of Prof. T.A. Jung at the University of Basel has reported on a new method that allows the physical state of just a few atoms or molecules within a network to be controlled.

The Innovation Award on Synchrotron Radiation 2018 went to Dr. Christian David, also from the Paul Scherrer Institute, and to Prof. Alexei Erko, who recently moved from the HZB to the Institute for Applied Photonics (IAP) in Berlin-Adlershof.

Our experiments, published in the September issue of Structural Dynamics, demonstrate the feasibility of time-resolved pump-multiprobe X-ray diffraction experiments on protein crystals using a split-and-delay setup which was temporarily installed at the LCLS X-ray Free Electron Laser.

At this year's annual meeting of the Swiss Nanoscience Institute (SNI) Jens Gobrecht, the former Head of LMN, received the SNI Honorary Membership.

Our image of a diamond structure was published on the cover page of the September 2018 issue of the journal "Materials Today". The corresponding paper reports on the nano-frabrication of micro-optical elements in diamond.

The spot size of a Fresnel Zone Plate lens is mainly determined by the zone widths of its outermost zone. It is therefore essential to fabricate zone plates with structures as small as possible for high-resolution X-ray microscopy. Researchers at the Laboratory for Micro- and Nanotechnology at the PSI have now developed Fresnel zone plates with zone widths well below 10 nm, down to 6.4 nm. These lenses are capable of pushing resolution in X-ray microscopy to the single-digit regime.

X-ray Free Electron Lasers (XFELs) combine the properties of synchrotron radiation (short wavelengths) and laser radiation (high lateral coherence, ultrashort pulse durations). These outstanding machines allow to study ultra-fast phenomena at an atomic level with unprecedented temporal resolution for answering the most intriguing open questions in biology, chemistry and physics.

PSI scientists have developed tailored diffractive X-ray optics for a free electron laser that induces an optical vortex in extreme ultraviolet radiation. The experiment facilitates the first demonstration of orbital angular momentum in radiation created by a free electron laser in the extreme ultraviolet regime, with an extraordinary clean and defined wavefront. In a collaborative effort with researchers from the FERMI free electron laser in Trieste, Italy and from the University of Nova Gorica in Slovenia, the wavefront of the intense beams carrying an orbtial angular momentum was characterized. Furthermore, a method to characterize the footprint of a focused beam from a free electron laser was refined based on ablation imprints in polymers and subsequent treatment with organic solvents. In this way, the sensitivity of the imprint method could be enhanced to a dynamic range of three orders of magnitude in a single shot.

PSI scientists have developed a new type of X-ray optics that allows for analyzing the emission in resonant inelastic x-ray scattering (RIXS) experiments. The new approach combines the energy dispersion with imaging capabilities. In a collaborative effort with research groups from Göttingen and Hamburg, two new classes of RIXS experiments, energy mapping and RIXS imaging, have been demonstrated.

Research experience from California's X-ray free-electron laser benefits SwissFEL. It's the camera that allows researchers to make extremely rapid processes visible: the X-ray free-electron laser. Currently, however, only three sites worldwide—in the US, Japan and South Korea—have facilities capable of carrying out such measurements. Two current articles in Science and Nature Communications co-authored by researchers now at the Paul Scherrer Institute PSI exemplify the kind of outstanding scientific work that can be carried out at such facilities, enabling new insights into the mechanisms of superconductors and magnetic switching in molecules. The measurements were conducted at the Linac Coherent Light Source (LCLS) free-electron laser in California. Press release PSI / Press release SLAC

Dr. Marcin Gorzny, Post-Doc at LMN in the PSI career return program recieved a poster prize at the Swiss Nanoconvention 2017 for his contribution entitled: "Silicon chip as lipid membrane holder for serial crystallography experiments".

For the first time, researchers have produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Paul Scherrer Institute, in collaboration with their research partners, published the findings in the journal Nature Communications.

A new method of material modification using 172 nm UV photons enables to fabricate ultra-smooth and self-optimized polymer surfaces. The method, published in Advanced Materials Technologies, was used in the production of high quality micro-optics to remove typical process flaws after a 2-photon-lithography process.

A novel type of diffractive lenses based on interlaced structures enable x-ray imaging at resolutions below 10 nm. The fabrication method and the test results of these novel x-ray lenses have been published in the journal Scientific Reports.

UV- and visible light-induced switching of enzymatic activity has been demonstrated using surface-grafted polymer brushes functionalized with microperoxidase MP-11 and spiropyran mojeties. Integration into an optofluidic device allowed reversible switching of the enzymatic activity under flow.

A nanofabricated low emittance field emitter array cathode was demonstrated for the first time, and successfully applied to observe the low-energy electron diffraction from suspended monolayer graphene. The work has an impact on the future development of compact X-ray free electron lasers, THz/RF vacuum electronic sources, and ultrafast electron imaging and diffraction experiments.

Sahan Ranamukhaarachchi, PhD student from UBC in Vancouver, won the 2016 "Brian L. Barge Award for Excellence in Microsystems Integration" for his work on a biosensing platform with integrated hollow microneedles carried out at PSI in 2015 in collaboration with Dr. Victor Cadarso and Dr. Celestino Padeste.

A promising system for painless and minimally-invasive therapeutic drug monitoring has been demonstrated. The proposed device combines biofunctionalized hollow microneedles with an optofluidic system to measure drug concentrations in volumes as small as 0.6 nL.

A method to precisely alter the quantum mechanical states of electrons within an array of quantum boxes has been developped by an international consortium also including PSI. The method can be used to investigate the interactions between various types of atoms and electrons, which is essential for future quantum technologies.