A5020592954- Advanced Condensed Matter Physics
- Physics of Superconductivity and Magnetism
- Organic and Molecular Conductors Research
- Topological Materials and Phenomena
- Rare-earth and actinide compounds
- Iron-based superconductors research
- Magnetism in coordination complexes
- Quantum, superfluid, helium dynamics
- Quantum and electron transport phenomena
- Superconducting Materials and Applications
- Magnetic and transport properties of perovskites and related materials
- Nuclear Materials and Properties
- Molecular Junctions and Nanostructures
- N-Heterocyclic Carbenes in Organic and Inorganic Chemistry
- Inorganic Chemistry and Materials
- High-pressure geophysics and materials
- Particle accelerators and beam dynamics
- Magnetic confinement fusion research
- Laser-Plasma Interactions and Diagnostics
- Organometallic Complex Synthesis and Catalysis
- Electronic and Structural Properties of Oxides
- Advanced Materials Characterization Techniques
- Advancements in Battery Materials
- Particle Accelerators and Free-Electron Lasers
- Particle Detector Development and Performance
Paul Scherrer Institute
2019-2024
University of Zurich
2021-2024
Rzeszów University
2018
Los Alamos National Laboratory
1998-2014
National High Magnetic Field Laboratory
1997-2012
Abstract Unconventional superconductors often feature competing orders, small superfluid density, and nodal electronic pairing. While unusual superconductivity has been proposed in the kagome metals A V 3 Sb 5 , key spectroscopic evidence remained elusive. Here we utilize pressure-tuned ultra-low temperature muon spin spectroscopy to uncover unconventional nature of RbV KV . At ambient pressure, observed time-reversal symmetry breaking charge order below...
The recently discovered vanadium-based kagome metals $A{\mathrm{V}}_{3}{\mathrm{Sb}}_{5}$ ($A$ = K, Rb, Cs) exhibit superconductivity at low temperatures and charge density wave (CDW) order high temperatures. A prominent feature of the ordered state in this family is that it breaks time-reversal symmetry (TRSB), which connected to underlying topological nature band structure. In work, a powerful combination zero-field high-field muon-spin rotation/relaxation used study signatures TRSB...
Abstract The recently discovered kagome superconductor CsV 3 Sb 5 ( T c ≃ 2.5 K) has been found to host charge order as well a non-trivial band topology, encompassing multiple Dirac points and probable surface states. Such complex phenomenologically rich system is, therefore, an ideal playground for observing unusual electronic phases. Here, we report anisotropic superconducting properties of by means transverse-field muon spin rotation μ SR) experiments. fits temperature dependences...
We report quantum oscillation measurements in SrFe2As2 - which is an antiferromagnetic parent of the iron-arsenide family superconductors known to become superconducting under doping and application pressure. The magnetic field temperature dependences oscillations between 20 55 T liquid helium range suggest that electronic excitations are those a Fermi liquid. show observed surface comprising small pockets consistent with formation spin-density wave. Our thus demonstrate high Tc...
We report muon spin rotation ($μ$SR) experiments together with first-principles calculations on microscopic properties of superconductivity in the kagome superconductor LaRu$_3$Si$_2$ $T_{\rm c}$ ${\simeq}$ 7K. find that calculated normal state band structure features a flat and Dirac as well van Hove points formed by Ru-$dz^2$ orbitals near Fermi level. Below c}$, $μ$SR reveals isotropic type-II superconductivity, which is robust against hydrostatic pressure up to 2 GPa. Intriguingly, ratio...
Abstract Charge ordered kagome lattices have been demonstrated to be intriguing platforms for studying the intertwining of topology, correlation, and magnetism. The recently discovered charge material ScV 6 Sn does not feature a magnetic groundstate or excitations, thus it is often regarded as conventional paramagnet. Here, using advanced muon-spin rotation spectroscopy, we uncover an unexpected hidden magnetism order. We observe enhancement internal field width sensed by muon ensemble,...
Abstract The kagome metals of the family A V 3 Sb 5 , featuring a unique structural motif, harbor an array intriguing phenomena such as chiral charge order and superconductivity. CsV is particular interest because it displays double superconducting dome in region temperature-pressure phase diagram where still present. However, microscopic origin unusual behavior remains unsolved issue. Here, to address it, we combine high-pressure, low-temperature muon spin relaxation/rotation with...
Abstract Magnetic topological phases of quantum matter are an emerging frontier in physics and materials science, which kagome magnets appear as a highly promising platform. Here, we explore magnetic correlations the recently identified system TbMn 6 Sn using muon spin rotation, combined with local field analysis neutron diffraction. Our studies identify out-of-plane ferrimagnetic structure slow fluctuations exhibit critical slowing down below $${T}_{{{{{{{{\rm{C1}}}}}}}}}^{* }$$ <mml:math...
Using ultrahigh magnetic fields up to 170 T and polarized midinfrared radiation with tunable wavelengths from 9.22 10.67 $\ensuremath{\mu}$m, we studied cyclotron resonance in large-area graphene grown by chemical vapor deposition. Circular polarization dependent studies reveal strong $p$-type doping for as-grown graphene, the dependence of on wavelength allows a determination Fermi energy. Thermal annealing shifts energy near Dirac point, resulting simultaneous appearance hole electron...
The pursuit of a unifying theory for non-BCS superconductivity has faced significant challenges. One approach to overcome such challenges is perform systematic investigations into superconductors containing \textit{d}-electron metals in order elucidate their underlying mechanisms. Recently, the Sc$_6M$Te$_2$ ($M$ = d-electron metal) family emerged as unique series isostructural compounds exhibiting across range $3d$, $4d$, and $5d$ electron systems. In this study, we employ muon spin...
We explore two methods for single-crystal growth of the theoretically proposed magnetic Weyl semimetals $R\mathrm{AlGe}$ ($R$ = Pr, Ce), which prove that a floating-zone technique, being both crucible- and flux-free, is crucial to obtain perfectly stoichiometric crystals. In contrast, crystals grown by flux-growth technique tend be Al-rich. further present structural elemental analyses, along with bulk magnetization electrical resistivity data on prepared technique. Both systems intended...
Abstract The kagome lattice is an intriguing and rich platform for discovering, tuning understanding the diverse phases of quantum matter, crucial advancing modern future electronics. Despite considerable efforts, accessing correlated at room temperature has been challenging. Using single-crystal X-ray diffraction, we discovered charge order above in La(Ru 1− x Fe ) 3 Si 2 ( = 0, 0.01, 0.05), where related to out-of-plane Ru atom displacements appears below T CO,I ≃ 400 K. secondary ordered...
Abstract The exploration of topological electronic phases that result from strong correlations is a frontier in condensed matter physics. One class systems currently emerging as platform for such studies are so-called kagome magnets based on transition metals. Using muon spin-rotation, we explore magnetic the magnet Co 3 Sn 2−x In x S 2 function In-doping, providing putative evidence an intriguing incommensurate helimagnetic (HM) state. Our results show that, while undoped sample exhibits...
Recently, the niobium (Nb) doped topological insulator ${\mathrm{Bi}}_{2}{\mathrm{Se}}_{3}$, in which finite magnetic moments of Nb atoms are intercalated van der Waals gap between ${\mathrm{Bi}}_{2}{\mathrm{Se}}_{3}$ layers, has been shown to exhibit both superconductivity with ${T}_{c}\ensuremath{\simeq}3$ K and surface states. Here we report on muon spin rotation experiments probing temperature field dependence effective penetration depth...
Unconventional superconductors often feature competing orders, small superfluid density, and nodal electronic pairing. While unusual superconductivity has been proposed in the kagome metals AV3Sb5, key spectroscopic evidence remained elusive. Here we utilize pressure-tuned (up to 1.85 GPa) ultra-low temperature (down 18 mK) muon spin spectroscopy uncover unconventional nature of RbV3Sb5. At ambient pressure, detect an enhancement width internal magnetic field distribution sensed by ensemble,...
The ability to efficiently control charge and spin in the cuprate high-temperature superconductors is crucial for fundamental research underpins technological development. Here, we explore tunability of magnetism, superconductivity, crystal structure stripe phase La[Formula: see text]Ba[Formula: text]CuO[Formula: text], with [Formula: text] = 0.115 0.135, by employing temperature-dependent (down 400 mK) muon-spin rotation AC susceptibility, as well X-ray scattering experiments under...
de Haas--van Alphen experiments on $\ensuremath{\alpha}\ensuremath{-}(\mathrm{B}\mathrm{E}\mathrm{D}\mathrm{T}\ensuremath{-}\mathrm{T}\mathrm{T}\mathrm{F}{)}_{2}\mathrm{KHg}(\mathrm{SCN}{)}_{4}$ in fields of up to 60 T reveal oscillations the $\ensuremath{\beta}$ frequency, a clear indication magnetic breakdown at well above kink transition. A study amplitude shows that gap between quasi-one-dimensional and quasi-two-dimensional Fermi-surface sheets is significantly smaller than predicted by...
We show that Shubnikov-de Haas oscillations in the interlayer resistivity of organic superconductor beta(")-(BEDT-TTF)2SF5CH2CF2SO3 become very pronounced magnetic fields approximately 60 T. The conductivity minima exhibit thermally activated behavior can be explained simply by presence a Landau gap, with quasi-one-dimensional Fermi surface sheets contributing negligibly to conductivity. This observation, together complete suppression chemical potential oscillations, is consistent an...
α -plutonium’s volume-corrected polycrystal elastic moduli were measured between 18K and the upper limit of its occurrence, near 400K. The two independent for a polycrystal—bulk shear—behave smoothly, indicating no phase transition. Both show same 50% increase on cooling, an order magnitude larger than in other metals. Debye temperature obtained from low-temperature moduli, 207K, significantly exceeds most previous estimates. Gruneisen parameter γ=5.3, dependence bulk modulus, is...
The breaking of time-reversal symmetry (TRS) in the normal state kagome superconductors $A$V$_{3}$Sb$_{5}$ stands out as a significant feature. Yet extent to which this effect can be tuned remains uncertain, crucial aspect grasp light varying details TRS observed through different techniques. Here, we employ unique low-energy muon spin rotation technique combined with local field numerical analysis study response function depth from surface single crystals RbV$_{3}$Sb$_{5}$ charge order and...