A5055678404- Rare-earth and actinide compounds
- Iron-based superconductors research
- Topological Materials and Phenomena
- Physics of Superconductivity and Magnetism
- Magnetic Properties of Alloys
- Advanced Condensed Matter Physics
- Magnetic properties of thin films
- Magnetic and transport properties of perovskites and related materials
- Intellectual Capital and Performance Analysis
- Inorganic Chemistry and Materials
- Corporate Taxation and Avoidance
- Multiferroics and related materials
- Graphene research and applications
- 2D Materials and Applications
- X-ray Diffraction in Crystallography
- Superconductivity in MgB2 and Alloys
- Metallurgical and Alloy Processes
- Crystallization and Solubility Studies
- Organic and Molecular Conductors Research
- Crystal Structures and Properties
- Quantum and electron transport phenomena
Max Planck Institute for Chemical Physics of Solids
2014-2024
Universidade Estadual de Campinas (UNICAMP)
2014-2023
Los Alamos National Laboratory
2019-2022
In the ferromagnetic (FM) Weyl semimetal CeAlSi both space-inversion and time-reversal symmetries are broken. Our quantum oscillation (QO) data indicate that FM ordering modifies Fermi-surface topology also leads to an unusual drop in QO amplitude. phase, we find a pressure-induced suppression of anomalous loop Hall effects. This cannot be explained based on electronic band structure or magnetic structure, which nearly pressure independent. Instead, show simplified model describing...
Our studies evidence an anisotropic magnetic order below $T_N = 32$~K. Susceptibility data in small fields of about 1~T reveal antiferromagnetic (AFM) for $H \perp c$, whereas \parallel c$ the are reminiscent a field-induced ferromagnetic (FM) structure. At low temperatures and field-dependent magnetization AC susceptibility metamagnetic transition at $H^+ 5$~T, which is absent c$. We assign this to from planar cycloidal spin structure fan-like arrangement above $H^+$. A fully FM polarized...
The Weyl semimetal CeAlGe is a promising material to study nontrivial topologies in real and momentum space due the presence of topological magnetic phase. Our results at ambient pressure show that electronic properties are extremely sensitive small stoichiometric variations. In particular, Hall effect (THE) present absent some samples almost identical chemical composition. application external favors antiferromagnetic ground state. It also induces THE where it was not visible pressure....
Abstract Progress in magnetoelectric materials is hindered by apparently contradictory requirements for time‐reversal symmetry broken and polar ferroelectric electronic structure common ferromagnets antiferromagnets. Alternative routes can be provided recent discoveries of a breaking anomalous Hall effect (AHE) noncollinear magnets altermagnets, but hitherto reported bulk are not polar. Here, the authors report observation spontaneous AHE doped AgCrSe 2 , layered semiconductor with an...
In this paper, the evolution of magnetic properties along series intermetallic compounds RCuBi2 (R = Ce, Pr, Nd, Gd, Sm) is discussed. These crystallize in a tetragonal ZrCuSi2 (P4/nmm) structure, and our single crystals grown from Bi-flux show no evidence for Cu-deficiency [Ye et al., Acta Crystallogr. C 52, 1325 (1996)] as previously reported R Ce. For Sm, we found an antiferromagnetic ordering at TN ∼ 16 K, 4.2 13.6 4.9 respectively. saw phase transition down to T 2 K. values clearly...
It is currently understood that high temperature superconductivity (SC) in the transition metal $(M)$ substituted iron arsenides $\mathrm{Ba}{({\mathrm{Fe}}_{1\ensuremath{-}x}{M}_{x})}_{2}{\mathrm{As}}_{2}$ promoted by magnetic excitations with wave vectors $(\ensuremath{\pi},0)$ or $(0,\ensuremath{\pi})$. known while a small amount of Co substitution lead to SC, same does not occur for Mn any value $x$. In this work,...
The possible existence of a sign-changing gap symmetry in BaFe2As2-derived superconductors (SC) has been an exciting topic research the last few years. To further investigate this subject we combine Electron Spin Resonance (ESR) and pressure-dependent transport measurements to magnetic pair-breaking effects on BaFe1.9M0.1As2 (M = Mn, Co, Cu Ni) single crystals. An ESR signal, indicative presence localized moments, is observed only for M Mn compounds, which display very low SC transition...
Abstract In this work we report the physical properties of series intermetallic compounds RAuBi2 (R = Ce, Pr, Nd, Gd, Sm) studied by means x-ray powder diffraction, magnetic susceptibility, heat capacity and electrical resistivity measurements. These were grown using metallic Bi self-flux technique they crystallize in a tetragonal ZrCuSi2 (P4/nmm) structure. Our single crystals show an antiferromagnetic ordering TN ≥ 2.3K for all measured compounds. The values dramatic breakdown De Gennes...
The polarization dependence of the near edge x-ray absorption spectroscopy (XANES) is an element specific probe to real-space distribution density unoccupied states in solid-state materials. In this paper, we present Fe and As $K$-edge experiments $\mathrm{Ba}{({\mathrm{Fe}}_{1\ensuremath{-}x}{M}_{x})}_{2}{\mathrm{As}}_{2}$ ($M=\mathrm{Mn}$, Co, $x=0.0$ 0.08). reveal a strong probed XANES spectra, which concerns mainly increase intensity electronic transitions when beam set out sample's $ab$...
We report the electronic and magnetic properties of stoichiometric CeAuBi$_{2}$ single crystals. At ambient pressure, orders antiferromagnetically below a N\'{e}el temperature ($T_{N}$) 19 K. Neutron diffraction experiments revealed an antiferromagnetic propagation vector $\hat{\tau} = [0, 0, 1/2]$, which doubles paramagnetic unit cell along $c$-axis. low temperatures several metamagnetic transitions are induced by application fields parallel to $c$-axis, suggesting that structure changes as...
Narrow-gap semiconductors are sought-after materials due to their potential for long-wavelength detectors, thermoelectrics, and more recently nontrivial topology. Here, we report the synthesis characterization of a new family narrow-gap semiconductors, R3Cd2As6 (R = La Ce). Single-crystal X-ray diffraction at room temperature reveals that As square nets distort Cd vacancies order in monoclinic superstructure. A putative charge-density ordered state sets 279 K La3Cd2As6 136 Ce3Cd2As6 is...
We have performed X-ray powder diffraction, magnetization, electrical resistivity, heat capacity and inelastic neutron scattering (INS) to investigate the physical properties of intermetallic series compounds CeCuBi$_{2-x}$Sb$_{x}$. These crystallize in a tetragonal structure with space group $P4/nmm$ present antiferromagnetic transition temperatures ranging from 3.6 K 16 K. Remarkably, magnetization easy axis changes along series, which is closely related variations crystalline electric...
Topological superconductors have long been sought for their potential use in quantum computing. The type-II Weyl semimetal ${\mathrm{MoTe}}_{2}$ is an obvious candidate, exhibiting a superconducting state below 500 mK at ambient pressure, but the question remains whether pairing conventional ${s}^{++}$ or topological ${s}^{+\ensuremath{-}}$. application of external pressure favors and suppresses structural transition from $1{T}^{\ensuremath{'}}$ to ${T}_{d}$. competition between two...
We report in-plane electrical resistivity studies of CeCuBi2 and LaCuBi2 single crystals under applied pressure. At ambient pressure, is a c-axis Ising antiferromagnet with transition temperature [Formula: see text] K. In magnetic field along the at K spin-flop takes place T. Applying pressure on suppresses T N slow rate. extrapolates to zero GPa. The critical displays maximum 6.8 low temperatures, zero-resistance superconducting state emerges upon application external having c 7 2.6 GPa in...
Raman scattering, synchrotron x-ray diffraction, specific heat, resistivity and magnetic susceptibility measurements were performed in Sr(Fe1-x Co x )2As2 [[Formula: see text]] single crystals with superconducting critical temperature [Formula: text] K two additional transitions at 132 152 observed both heat data. A quasielastic signal B 2g symmetry (tetragonal cell) associated electronic nematic fluctuations is observed. Crucially, this shows maximum intensity K, marking the transition...
We report electrical transport measurements on ${\mathrm{CaMn}}_{2}{\mathrm{Bi}}_{2}$ single crystals under applied pressure. At ambient pressure and high temperatures, behaves as a single-band semimetal hosting N\'eel order at ${T}_{N}=150$ K. low multiband behavior emerges along with an activated typical of degenerate semiconductors. The activation gap is estimated to be $\mathrm{\ensuremath{\Delta}}\ensuremath{\sim}20$ Applied not only favors the antiferromagnetic rate 0.40(2) K/kbar, but...
At ambient pressure, HfTe$_{5}$ is a material at the boundary between weak and strong topological phase, which can be tuned by changes in its crystalline structure or application of high magnetic fields. It exhibits Lifshitz transition upon cooling, three-dimensional (3D) quantum Hall effect (QHE) plateaus observed low temperatures. Here, we have investigated electrical transport properties under hydrostatic pressure up to 3 GPa. We find pressure-induced crossover from semimetallic phase...
At ambient pressure, <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:msub><a:mi>HfTe</a:mi><a:mn>5</a:mn></a:msub></a:math> is a material at the boundary between weak and strong topological phase, which can be tuned by changes in its crystalline structure or application of high magnetic fields. It exhibits Lifshitz transition upon cooling, three-dimensional (3D) quantum Hall effect (QHE) plateaus observed low temperatures. Here, we have investigated electrical transport properties...
We report a combined study of external pressure and Cu-substitution on BaFe2As2 single crystals grown by the in-flux technique. At ambient pressure, is known to suppress spin density wave (SDW) phase in pure BaFe2As2(T(SDW) ≈ 140 K) induce superconducting (SC) dome with maximum transition temperature T(c)(max) ≃ 4.2 K. This much lower than T(c) ∼ 15-28 K achieved case Ru, Ni Co substitutions. Such attributed Cu(2+) magnetic pair-breaking effect. The latter strongly suppressed applied as...
In this work, we report x-ray powder diffraction, elemental analysis, electrical resistivity, magnetic susceptibility, specific heat, and electron spin resonance (ESR) in single crystals of ${\mathrm{Sr}}_{1\text{\ensuremath{-}}x}{\mathrm{Eu}}_{x}{\mathrm{Fe}}_{2}{\mathrm{As}}_{2}$. We observed a breakdown the previously reported scaling between ${\mathrm{Eu}}^{2+}$ Korringa relaxation rate obtained from ESR density wave temperature evolution for Sr-rich samples. This result suggests...
We study the interplay between electronic correlations and hybridization in low-energy structure of CaMn[Formula: see text]Bi[Formula: text], a candidate hybridization-gap semiconductor. By employing DFT+U approach we find both antiferromagnetic Néel order band gap good agreement with corresponding experimental values. Under hydrostatic pressure, crossover from to charge-transfer insulting physics due delicate balance correlations. Increasing pressure above [Formula: text] GPa simultaneous...
Progress in magnetoelectric materials is hindered by apparently contradictory requirements for time-reversal symmetry broken and polar ferroelectric electronic structure common ferromagnets antiferromagnets. Alternative routes could be provided recent discoveries of a breaking anomalous Hall effect noncollinear magnets altermagnets, but hitherto reported bulk are not polar. Here, we report the observation spontaneous doped AgCrSe$_2$, layered semiconductor with an antiferromagnetic coupling...
We report the evolution of magnetic properties Ce2Rh1-xIrxIn8-yCdy single crystals. In particular, for Ce2Rh0.5Ir0.5In8 (TN=2.0K) and Ce2Rh0.5Ir0.5In7.79Cd0.21 (TN=4.2K), we have solved structure these compounds using single-crystal neutron diffraction experiments. Taking Ce2RhIn8 heavy-fermion antiferromagnet as a reference, identified no changes in q=12,12,0 wave vector; however, direction ordered Ce3+ moments rotates toward ab plane, under influence both dopants. By constraining analysis...