A5053308546- Quantum, superfluid, helium dynamics
- Physics of Superconductivity and Magnetism
- Rare-earth and actinide compounds
- Cold Atom Physics and Bose-Einstein Condensates
- Atomic and Subatomic Physics Research
- Topological Materials and Phenomena
- High-pressure geophysics and materials
- Inorganic Chemistry and Materials
- Advanced Condensed Matter Physics
- X-ray Spectroscopy and Fluorescence Analysis
- Advanced Chemical Physics Studies
- Iron-based superconductors research
- Advancements in Photolithography Techniques
- Organic and Molecular Conductors Research
- Catalysis and Oxidation Reactions
- Magnetic properties of thin films
- Advanced X-ray Imaging Techniques
Paul Scherrer Institute
2021-2024
Lancaster University
2016-2023
Abstract Tuning of electronic density-of-states singularities is a common route to unconventional metal physics. Conceptually, van Hove are realized only in clean two-dimensional systems. Little attention has therefore been given the disordered (dirty) limit. Here, we provide magnetotransport study dirty metamagnetic system calcium-doped strontium ruthenate. Fermi liquid properties persist across transition, but with an unusually strong variation Kadowaki-Woods ratio. This revealed by...
Abstract The ground state of a fermionic condensate is well protected against perturbations in the presence an isotropic gap. Regions gap suppression, surfaces and vortex cores which host Andreev-bound states, seemingly lift that strict protection. Here we show superfluid 3 He role bound states more subtle: when macroscopic object moves at velocities exceeding Landau critical velocity, little to no bulk pair breaking takes place, while damping observed originates from covering moving object....
A spatially modulated superconducting state, known as pair density wave (PDW), is a tantalizing state of matter with unique properties. Recent scanning tunneling microscopy (STM) studies revealed that spin-triplet superconductor UTe
We report on a novel technique to measure quartz tuning forks, and possibly other vibrating objects, in quantum fluid using multifrequency lock-in amplifier. The allows the resonance curve of object much faster than conventional single frequency amplifier technique. Forks with frequencies 12 kHz 16 were excited measured electro-mechanically either at or up 40 different simultaneously around same mechanical mode. response each fork was identical for both methods validates use probe properties...
Understanding the temperature dependence of thermal boundary resistance, or Kapitza between liquid helium and sintered metal has posed a problem in low physics for decades. In ballistic regime superfluid $^{3}$He-B, we find resistance can be described via scattering excitations (quasiparticles) with macroscopic geometric area, rather than metal's microscopic area. We estimate that quasiparticle needs on order 1000 collisions to successfully thermalise sinter. Finally, is approximately...
Abstract Modern techniques for the investigation of correlated materials in time domain combine selective excitation THz frequency range with probing coupled structural, electronic and magnetic degrees freedom using x-ray scattering techniques. Cryogenic sample temperatures are commonly required to prevent thermal occupation low energy modes access relevant material ground states. Here, we present a chamber optimized high-field (resonant) diffraction at between 5 500 K. Directly connected...
A spatially modulated superconducting state at zero magnetic field, known as pair density wave (PDW), is a tantalizing of matter with unique properties. PDWs have been observed in diverse spin-singlet superconductors ranging from high-temperature cuprate and Fe-based to kagome two-dimensional chalcogenide compounds. Recent scanning tunneling microscopy (STM) studies reveal that spin-triplet superconductor UTe$_2$ hosts an unprecedented PDW whose wavevectors are indistinguishable preceding...
We investigate the damping experienced by quartz tuning fork resonators in normal and superfluid $^{3}\mathrm{He}$ as a function of their resonance frequency from 22 to 250 kHz contrast it with behavior forks $^{4}\mathrm{He}$. For our set low both fluids is well described existing hydrodynamic models. find that acoustic emission becomes dominating dissipation mechanism at resonator frequencies exceeding approximately 100 kHz. Our results show model used $^{4}\mathrm{He}$ fluid also...
Steering x-ray beams from the source towards experiment without distorting their wavefront defines extraordinary high-quality requirements on production of optics. We report how this demand settled with in situ shot-to-shot sensing optimization KB optics at SwissFEL beamlines. This contribution presents methodology that combines moir´e interferometry and single-phase-grating Talbot interferometry. discuss an online Kirkpatrick-Baez (KB) test plan Cristallina beamline based single phase...