Publications by authors named "Orain J"

The electronic ground state of iron-based materials is unusually sensitive to electronic correlations. Among others, its delicate balance is profoundly affected by the insertion of magnetic impurities in the FeAs layers. Here, we address the effects of Fe-to-Mn substitution in the non-superconducting Sm-1111 pnictide parent compound via a comparative study of SmFe[Formula: see text]Mn[Formula: see text]AsO samples with [Formula: see text] 0.

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Background: Early inhibition of entry and replication of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a very promising therapeutic approach. Polyclonal neutralizing antibodies offers many advantages such as providing immediate immunity, consequently blunting an early pro-inflammatory pathogenic endogenous antibody response and lack of drug-drug interactions. By providing immediate immunity and inhibiting entry into cells, neutralizing antibody treatment is of interest for patient with COVID-19-induced moderate pneumonia.

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We present a combination of thermodynamic and dynamic experimental signatures of a disorder driven dynamic cooperative paramagnet in a 50% site diluted triangular lattice spin-1/2 system: Y_{2}CuTiO_{6}. Magnetic ordering and spin freezing are absent down to 50 mK, far below the Curie-Weiss scale (-θ_{CW}) of ∼134  K. We observe scaling collapses of the magnetic field and temperature dependent magnetic heat capacity and magnetization data, respectively, in conformity with expectations from the random singlet physics.

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We report on muon spin rotation experiments probing the magnetic penetration depth λ() in the layered superconductors in 2H-NbSe and 4H-NbSe. The current results, along with our earlier findings on 1T'-MoTe (Guguchia ), demonstrate that the superfluid density scales linearly with in the three transition metal dichalcogenide superconductors. Upon increasing pressure, we observe a substantial increase of the superfluid density in 2H-NbSe, which we find to correlate with .

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We report muon spin rotation and magnetization measurements under pressure on Fe_{1+δ}Se_{1-x}S_{x} with x≈0.11. Above p≈0.

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Objective: Staphylococcusaureus is involved in around 20% of nosocomial pneumonia cases. Vancomycin used to be the reference antibiotic in this indication, but new molecules have been commercialized, such as linezolid. Previous studies comparing vancomycin and linezolid were based on models.

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Article Synopsis
  • The study examines various magnetic properties of the Kitaev honeycomb iridate Cu2IrO3, revealing that even with chemical disorders, there are no signs of spin glass behavior down to 260 mK.
  • Despite the lack of static magnetism, the results indicate dynamic spin behavior, as shown by muon spin relaxation measurements.
  • Scaling relations in magnetic susceptibility and magnetization suggest the influence of bond randomness, but specific heat measurements point to unexpected low-lying excitations, highlighting the complex effects of quenched disorder in this spin system.
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Temperature-pressure phase diagram of the Kitaev hyperhoneycomb iridate β-Li_{2}IrO_{3} is explored using magnetization, thermal expansion, magnetostriction, and muon spin rotation measurements, as well as single-crystal x-ray diffraction under pressure and ab initio calculations. The Néel temperature of β-Li_{2}IrO_{3} increases with the slope of 0.9  K/GPa upon initial compression, but the reduction in the polarization field H_{c} reflects a growing instability of the incommensurate order.

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The compound SrCeFBiS belongs to the intensively studied family of layered BiS superconductors. It attracts special attention because superconductivity at T  = 2.8 K was found to coexist with local-moment ferromagnetic order with a Curie temperature T  = 7.

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In the vanadium oxyfluoride compound (NH_{4})_{2}[C_{7}H_{14}N][V_{7}O_{6}F_{18}] (DQVOF), the V^{4+} (3d^{1}, S=1/2) ions realize a unique, highly frustrated breathing kagome lattice composed of alternately sized, corner-sharing equilateral triangles. Here we present an ^{17}O NMR study of DQVOF, which isolates the local susceptibility of the breathing kagome network. By a fit to series expansion, we extract the ratio of the interactions within the breathing kagome plane, J_{∇}/J_{Δ}=0.

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We show using detailed magnetic and thermodynamic studies and theoretical calculations that the ground state of Ba_{3}ZnIr_{2}O_{9} is a realization of a novel spin-orbital liquid state. Our results reveal that Ba_{3}ZnIr_{2}O_{9} with Ir^{5+} (5d^{4}) ions and strong spin-orbit coupling (SOC) arrives very close to the elusive J=0 state but each Ir ion still possesses a weak moment. Ab initio density functional calculations indicate that this moment is developed due to superexchange, mediated by a strong intradimer hopping mechanism.

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Introduction: Tuberculosis disease warrants standard therapeutic management as detailed in a guide published by the High Authority for Health (HAS) following the publication of the Public Health Law in 2004.

Methods: The medical services of the régime social des indépendants (RSI) carried out a national survey by targeting patients who, in 2011, were reimbursed for tuberculosis treatment or were admitted for long-term tuberculosis disease. Their physicians were contacted to detail the care pathway and treatment they had received.

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Na_{4}Ir_{3}O_{8} is a unique case of a hyperkagome 3D corner sharing triangular lattice that can be decorated with quantum spins. It has spurred a lot of theoretical interest as a spin liquid candidate. We present a comprehensive set of NMR data taken on both the ^{23}Na and ^{17}O sites.

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The vanadium oxyfluoride [NH(4)](2)[C(7)H(14)N][V(7)O(6)F(18)] (DQVOF) is a geometrically frustrated magnetic bilayer material. The structure consists of S = 1/2 kagome planes of V(4+) d(1) ions with S = 1 V(3+) d(2) ions located between the kagome layers. Muon spin relaxation measurements demonstrate the absence of spin freezing down to 40 mK despite an energy scale of 60 K for antiferromagnetic exchange interactions.

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