Scientific Highlights

Moeckli et al

Two scenarios for superconductivity in CeRh2As2

CeRh2As2, a nonsymmorphic heavy fermion material, was recently reported to host a remarkable temperature versus z-axis magnetic-field phase diagram with two superconducting phases. In this material, the two inequivalent Ce sites per unit cell, related by inversion symmetry, introduce a sublattice structure corresponding to an extra internal degree of freedom. In this work, we propose a classification of the possible superconducting states in CeRh2As2 from the two Ce-sites' perspective.

 

Manuel Grimm
•Future Technologies
•5 min

New blueprint for more stable quantum computers

Quantum research

PSI researchers have shown how faster and better defined quantum bits can be created. The central elements are magnetic atoms from the class of so-called rare-earth metals, selectively implanted into the crystal lattice of a material.

Dr. Ioannis (John) Mantzaras

Fellow Award for Dr. Mantzaras

The prestigious Fellow Award “Fellow of The Combustion Institute” was allotted to Dr. Mantzaras for “Pioneering Experimental and Modeling Research in Hetero-/Homogeneous and Catalytic Combustion”. The combustion activities at LSM emphasize on non-intrusive laser-based measurements in a high-pressure optically accessible catalytic reactor, while the modeling activities encompass advanced multidimensional numerical simulations and theoretical work based on activation energy asymptotics.

Benefit of random testing

Benefit of random testing

With the imminent relaxation of socio-economic restrictions, it becomes vital to assess its effect on the prevalence of acute infections within the population, as rapidly as possible. Currently available monitoring instruments for the COVID-19 pandemic have an inherent time delay of about 14 days, as they rely on confirmed infections, hospitalizations, and death numbers. These methods give Reff(t) (the number of infections caused by a single infected person), but their delay is a significant disadvantage when restrictions are released. If after relaxation, Reff(t) rises above 1, one will not be able to react adequately before two weeks have passed during which time the prevalence could significantly rise. Here, we propose the use of random testing to shorten this reaction time, by obtaining direct and modeling dependent information on Reff(t). Through random testing of between 2500 and 20000 people per day, we find that over periods significantly shorter than two weeks, it becomes possible to detect a dangerous increase in Reff with reasonable confidence.

Teaser Interview Adelmann
•Future Technologies
•5 min

Simulation: The third pillar of science

Biology

PSI researchers simulate and model large research facilities as well as experiments, for example, in the materials and biological sciences. Andreas Adelmann, head of PSI's Laboratory for Scientific Computing and Modelling, explains how they do it.

Dr. Andreas Adelmann
•Future Technologies
•6 min

Modelling and simulation pay off

Biology Nuclear energy

Researchers in PSI's Laboratory for Scientific Computing and Modelling solve the most complex problems through a combination of theory, modelling, and high-performance computing. With powerful computers, they simulate the smallest molecules or large research facilities.

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Spin fluctuation induced Weyl semimetal state in the paramagnetic phase of EuCd2As2

Weyl fermions as emergent quasiparticles can arise in Weyl semimetals (WSMs) in which the energy bands are nondegenerate, resulting from inversion or time-reversal symmetry breaking. Nevertheless, experimental evidence for magnetically induced WSMs is scarce. Here, using photoemission spectroscopy, we observe that the degeneracy of Bloch bands is already lifted in the paramagnetic phase of EuCd2As2. We attribute this effect to the itinerant electrons experiencing quasi-static and quasi–long-range ferromagnetic fluctuations.

Christopher Mudry

EPFL Adjunct Professorship to Christopher Mudry

Dr Christopher Mudry, who joined PSI in 1999 and is Research Group Leader of the Condensed Matter Theory Group at PSI since 2009, was awarded the title of Adjunct Professor at EPF Lausanne with the following citation. "Dr Christopher Mudry is a highly acclaimed theoretical physicist. He is regarded as one of the world’s leading experts on the quantum field theory of condensed matter and in the rapidly developing field of the topological properties of matter."