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Related papers: {\alpha}-FeAs-free SmFeAsO1-xFx by low temperature…

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The accurate interpretation of experiments with matter at extreme densities and pressures is a notoriously difficult challenge. In a recent work [T.~Dornheim et al., Nature Comm. (in print), arXiv:2206.12805], we have introduced a formally…

We use a deep XMM-Newton Reflection Grating Spectrometer observation to examine the X-ray emission from the core of the Centaurus cluster of galaxies. We clearly detect Fe-XVII emission at four separate wavelengths, indicating the presence…

Astrophysics · Physics 2009-11-13 J. S. Sanders , A. C. Fabian , S. W. Allen , R. G. Morris , J. Graham , R. M. Johnstone

Phonons in single crystals of PrFeAsO_{1-y} are investigated using high-resolution inelastic x-ray scattering and ab initio pseudopotential calculations. Extensive measurements of several samples at temperatures spanning the magnetic…

Strongly Correlated Electrons · Physics 2011-08-12 T. Fukuda , A. Q. R. Baron , H. Nakamura , S. Shamoto , M. Ishikado , M. Machida , H. Uchiyama , A. Iyo , H. Kito , J. Mizuki , M. Arai , H. Eisaki

In this work we present the results of an inelastic x-ray scattering experiment detailing the behavior of the transverse acoustic [110] phonon in BaFe2As2 as a function of temperature. When cooling through the structural transition…

Superconductivity · Physics 2012-01-04 Jennifer L. Niedziela , D. Parshall , K. A. Lokshin , A. S. Sefat , A. Alatas , T. Egami

The 57Fe M\"ossbauer spectroscopy was applied to an iron-based layered superconductor LaO0.89F0.11FeAs with a transition temperature of 26 K and its parent material LaOFeAs. Throughout the temperature range from 4.2 to 298 K, a singlet…

Superconductivity · Physics 2008-10-10 S. Kitao , Y. Kobayashi , S. Higashitaniguchi , M. Saito , Y. Kamihara , M. Hirano , T. Mitsui , H. Hosono , M. Seto

We present measurements of the thermal expansion coefficient alpha of polycrystalline LaFeAsO1-xFx (x <= 0.1). The magnetic and structural transitions of the samples with x <= 0.04 give rise to large anomalies in alpha(T), while the onset…

Superconductivity · Physics 2015-05-13 L. Wang , U. Kohler , N. Leps , A. Kondrat , M. Nale , A. Gasparini , A. de Visser , G. Behr , C. Hess , R. Klingeler , B. Buchner

Thermal stability of hydrogenated amorphous Si/Ge multilayers has been investigated by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Small-Angle X-Ray Diffraction (SAXRD) techniques. Amorphous H-Si/Ge…

Materials Science · Physics 2009-02-11 A. Csik , M. Serenyi , Z. Erdelyi , A. Nemcsics , C. Cserhati , G. A. Langer , D. L. Beke , C. Frigeri , A. Simon

Here we report the synthesis and basic characterization of LaFe1-xCoxAsO for several values of x. The parent phase LaFeAsO orders antiferromagnetically (TN ~ 145 K). Replacing Fe with Co is expected to both electron dope the system and…

Superconductivity · Physics 2009-11-13 Athena S. Sefat , Ashfia Huq , Michael A. McGuire , Rongying Jin , Brian C. Sales , David Mandrus

Superconducting fluctuations (SF) in SmFeAsO$_{0.8}$F$_{0.2}$ (characterized by superconducting transition temperature $T_{c} \simeq 52.3$ K) are investigated by means of isothermal high-resolution dc magnetization measurements. The…

Superconductivity · Physics 2012-04-25 G. Prando , A. Lascialfari , A. Rigamonti , L. Romanò , S. Sanna , M. Putti , M. Tropeano

FeXMn1-XS (0 <x< 0.3) synthesized on the basis of {\alpha}-MnS are the novel Mott-type substances with the rock salt structure. Neutron diffraction study shows that the shift of the Neel temperature of these materials from 150 (x = 0) to…

The low-temperature antiferromagnetic state of the Sm-ions in both nonsuperconducting SmFeAsO and superconducting SmFeAsO$_{0.9}$F$_{0.1}$ single crystals was studied by magnetic torque, magnetization, and magnetoresistance measurements in…

Effects of the Co substitution have been observed on the structural, magnetic and magneto-transport properties of Fe2-xCoxMnSi alloy. Curie temperature (TC) and saturation magnetization (MS) of these alloys increased linearly with the Co…

Strongly Correlated Electrons · Physics 2015-12-01 Lakhan Bainsla , K. G. Suresh , M. Manivel Raja , A. K. Nigam

Thin films of Ti1-xFexO2 (x=0 and 0.05) have been prepared on sapphire substrates by spin-on technique starting from metal organic precursors. When heat treated in air at 550 and 700 degrees C respectively, these films present pure anatase…

Materials Science · Physics 2009-11-10 R. Suryanarayanan , V. M. Naik , P. Kharel , P. Talgala , R. Naik

We report the theoretical study of the flux-lattice melting in the novel iron-based superconductor $LaO_{0.9}F_{0.1}FeAs$ and $LaO_{0.925}F_{0.075}FeAs$. Using the Hypernetted-Chain closure and an efficient algorithm, we calculate the…

Superconductivity · Physics 2009-11-13 Jian-Ping Lv , Qing-Hu Chen

We report the successful growth of high quality single crystals of LiFeAs with lateral sizes up to 5 x 5 mm2 by the Sn-flux method. Electrical resistivity studies reveal that the superconducting onset temperature is 18.2 K with a transition…

Superconductivity · Physics 2010-10-20 Bumsung Lee , Seunghyun Khim , Jung Soo Kim , G. R. Stewart , Kee Hoon Kim

Recent demonstrations on manipulating antiferromagnetic (AF) order have triggered a growing interest in antiferromagnetic metal (AFM), and potential high-density spintronic applications demand further improvements in the anisotropic…

Mesoscale and Nanoscale Physics · Physics 2018-07-12 Youngseok Kim , Moon Jip Park , David G. Cahill , Matthew J. Gilbert

Pure phases of a new oxyarsenide superconductor of the nominal composition CeOFe0.9Co0.1As was successfully synthesized by solid state reaction in sealed silica ampoules at 1180 C. It crystallizes in the layered tetragonal ZrCuSiAs type…

Superconductivity · Physics 2009-03-24 J. Prakash , S. J. Singh , S. Patnaik , A. K. Ganguli

The synthesis and properties of LiFeAs, a high-Tc Fe-based superconducting stoichiometric compound, are reported. Single crystal x-ray studies reveal that it crystallizes in the tetragonal PbFCl type (P4/nmm) with a=3.7914(7) A and…

Superconductivity · Physics 2008-08-25 Joshua H. Tapp , Zhongjia Tang , Bing Lv , Kalyan Sasmal , Bernd Lorenz , Paul C. W. Chu , Arnold M. Guloy

We report an easy and versatile one-step route of synthesis for newly discovered Fe based superconductor LaFeAsO1-d with d = 0.0 to 0.15. Instead of widely used high-pressure-high-temperature (HPHT) synthesis, we applied the normal…

The crystal structure and magnetic properties of MnCoxFe1-xSi (x=0-0.5) compounds were investigated. With increasing Fe content, the unit cell changes anisotropically and the magnetic property evolves gradually: Curie temperature decreases…