Energy transition

Shifting away from nuclear energy, expanding solar and wind power, generating energy from biomass, reducing energy consumption. Switzerland is committed to becoming climate-neutral by 2050. An ambitious goal, which has become more urgent than ever due to the increasingly challenging geopolitical situation. How can a sustainable and resilient energy supply for Switzerland be established over the coming years? What's the optimal way to use renewable energy sources? What new technologies are especially promising? At PSI, researchers are seeking answers to these crucial questions.

Grinenko et al

Split superconducting and time-reversal symmetry-breaking transitions in Sr2RuO4 under stress

Strontium ruthenate (Sr2RuO4) continues to present an important test of our understanding of unconventional superconductivity, because while its normal-state electronic structure is known with precision, its superconductivity remains unexplained. There is evidence that its order parameter is chiral, but reconciling this with recent observations of the spin part of the pairing requires an order parameter that is either finely tuned or implies a new form of pairing. Therefore, a definitive resolution of whether the superconductivity of Sr2RuO4 is chiral is important for the study of superconductivity.

 

Table of Content

Optimization of Nanofluidic Devices for Geometry-Induced Electrostatic Trapping

Single particle studies play an important role in understanding their physical and chemical properties. Electrostatic trapping is on one such robust method that allows for a contact-free high-throughput single nanoparticle trapping in an aqueous environment in a nanofluidic device. However, finding an optimum design solution for stiffer single particle trapping for different particles is a cumbersome process. This work presents all crucial geometrical parameters required to tune the trapping efficiency of the device, and their impact. Furthermore, the work enables to quickly identify and optimize nanofluidic devices design for stronger single particle confinement using numerical simulations, saving the massive experimental time required for device optimization.

LRG Teaser

Conduction control in nanoparticles

Light induced propagation strain pulse, converting nanoparticles of Ti3O5 from semiconducting to metallic phase.

LIn et al PRL

Strong Superexchange in a d^(9−δ) Nickelate Revealed by Resonant Inelastic X-Ray Scattering

The discovery of superconductivity in a d9−δ nickelate has inspired disparate theoretical perspectives regarding the essential physics of this class of materials. A key issue is the magnitude of the magnetic superexchange, which relates to whether cuprate-like high-temperature nickelate superconductivity could be realized. We address this question using Ni L-edge and O K-edge spectroscopy of the reduced d9−1/3 trilayer nickelates R4Ni3O8 (where R = La, Pr) and associated theoretical modeling.

 

Platinum chloride in aqueous solution promotes the dispersion of large gold nanoparticles (>70 nm) on carbon

Sustainable Synthesis of Bimetallic Single Atom Gold-Based Catalysts with Enhanced Durability in Acetylene Hydrochlorination

Platinum chloride in aqueous solution promotes the dispersion of large gold nanoparticles (>70 nm) on carbon carriers into single atoms, forming bimetallic single-atom catalysts with improved resistance against sintering at temperatures up to 800 K and under the harsh reductive reaction conditions of acetylene hydrochlorination, leading to improved lifetime in this reaction. To rationalize these observations, this study, led by ETH Zurich, utilized X-ray adsorption spectroscopy conducted at the SuperXAS beamline of the SLS to provide insights into the degree of gold dispersion and the structure of the isolated metal sites in the bimetallic catalysts.

SWEET

SWEET Program, Research challenge 4: Sustainability at the heart of a resilient Swiss energy system

The results have been announced of the first call for proposals in the new energy research programme SWEET (Swiss Energy Research for the Energy Transition). An international panel of experts has awarded the contract to four consortia. The host institutions of these research consortia are ETHZ, EPFL, the University of Geneva and the PSI. Over the next six to eight years, they will work on their research tasks in trans- and interdisciplinary projects.

Valsecchi et al

Decomposing Magnetic Dark-Field Contrast in Spin Analyzed Talbot-Lau Interferometry: A Stern-Gerlach Experiment without Spatial Beam Splitting

We have recently shown how a polarized beam in Talbot-Lau interferometric imaging can be used to analyze strong magnetic fields through the spin dependent differential phase effect at field gradients. While in that case an adiabatic spin coupling with the sample field is required, here we investigate a nonadiabatic coupling causing a spatial splitting of the neutron spin states with respect to the external magnetic field. This subsequently leads to no phase contrast signal but a loss of interferometer visibility referred to as dark-field contrast.

 

Xu et al

Unconventional Transverse Transport above and below the Magnetic Transition Temperature in Weyl Semimetal EuCd2As2

As exemplified by the growing interest in the quantum anomalous Hall effect, the research on topology as an organizing principle of quantum matter is greatly enriched from the interplay with magnetism. In this vein, we present a combined electrical and thermoelectrical transport study on the magnetic Weyl semimetal EuCd2As2. Unconventional contribution to the anomalous Hall and anomalous Nernst effects were observed both above and below the magnetic transition temperature of EuCd2As2, indicating the existence of significant Berry curvature.

 

pldcdw_teaser.png

Structural involvement in the melting of the charge density wave in 1T-TiSe2

The authors find using resonant and non-resonant x-ray diffraction on an x-ray free electron laser that the structural distortion and the underlying electronic structure of the charge density wave in TiSe2 show different energetics at ultrafast timescales. This indicates that the lattice distortion stabilizes the charge density wave.

Water teaser

Ultrafast calorimetry of deeply supercooled water

FEL-based ultrafast calorimetry measurements show enhancement and maximum in the isobaric specific-heat.

Wennmacher_Julian_Defense

Congratulations to Julian Wennmacher!

On February 10th, 2021, Julian Wennmacher defended his PhD entitled "Developing electron crystallography to elucidate the location of functional sites in zeolites" at ETH Zurich. Congratulations!

 

Robert Kaelin

New group member

Robert Kälin officially joins the Quantum Technologies  group as technician of the Cristallina endstation.

SRF

Christian Bauer interviewed on Electric Mobility at the Kassensturz program by SRF

SRF interviewed Christian Bauer, a scientist at PSI's Laboratory for Energy Systems Analysis who specialises in life cycle and sustainability analyses, on Electric Mobility at the program Kassensturz

Dubray_Florent

Welcome Florent Dubray

On Feb 1st, a new postdoc, Florent Dubray will start in our group. He finished his PhD on the synthesis, characterization and catalytic applications of metal containing zeolites at the ENSI in Caen.

He will work on the (new) SYNFUEL project (a PSI initiative to make sustainable jet fuel) converting methanol into jet fuel over modified zeolite catalysts.

TCS

TCS Switzerland Passenger Cars platform extended with Life Cycle Carbon footprint from PSI-TA

TCS Switzerland has extended its passenger car search and comparison platform by adding the life cycle carbon footprint quantified by PSI-TA.