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

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Here we report the superconductivity in the LaFeAsO1-xFx system prepared by high pressure synthesis. The highest onset superconducting transition temperature (Tc) in this La-based system is 41.0 K with the nominal composition of…

Polycrystalline samples and single crystals of SmFeAs1-xPxO1-y were synthesized and grown employing different synthesis methods and annealing conditions. Depending on the phosphorus and oxygen content, the samples are either magnetic or…

The structural and microstructural properties of the Sm(Fe1-xRux)As(O0.85F0.15) system were investigated by means of high-resolution synchrotron X-ray powder diffraction between 10 K and 300 K. The tetragonal to orthorhombic structural…

Superconductivity · Physics 2018-11-16 A. Martinelli

Establishing a complete electronic phase diagram for REFeAsO (RE = rare earth, RE1111) ironbased superconductors has remained experimentally challenging. Here, we report a systematic investigation of PrFeAsO1-xFx over the full nominal…

We demonstrate the fabrication of superconducting SmFeAsO1-xFx (Sm-1111) wires by using the ex-situ powder-in-tube technique. Sm-1111 powder and a binder composed of SmF3, samarium arsenide, and iron arsenide were used to synthesize the…

Here, we report the synthesis and characterization of sulphur-substituted iron telluride i.e. FeTe1-xSx; (x = 0-30 %) system and study the impact of low temperature oxygen (O2) annealing as well. Rietveld analysis of room temperature x-ray…

Superconductivity · Physics 2015-05-19 V. P. S. Awana , Anand Pal , Arpita Vajpayee , Bhasker Gahtori , H. Kishan

We report the resistivity of a series of fluorine-doped SmFeAsO1-xFx polycrystalline superconductors in magnetic fields up to 60T. For underdoped samples (x < 0.15), the low temperature resistive state is characterized by pronounced…

The difference in thermal stability of F- and H- in 1111-type iron based superconductors, allows selective hydrogen elimination from non-superconductive CaFeAsF0.8H0.2 by thermal annealing. The analyzed chemical composition of the resulting…

Superconductivity · Physics 2013-09-27 Taku Hanna Yoshinori Muraba Satoru Matsuishi , Hideo Hosono

We have prepared the newly discovered Fe-based superconducting material $\rm LaO_{1-x}F_xFeAs$ ($0\leq x\leq 0.2$) in polycrystalline form and have investigated the samples by means of structural, thermodynamic and transport measurements.…

A series of polycrystalline SmO1-xFxFeAs bulks (x=0.15, 0.2, 0.3 and 0.4) were prepared by the conventional solid state reaction. Resistivity, susceptibility, magnetic hysteresis, critical current density and microstructure of these samples…

Superconductivity · Physics 2009-11-13 Lei Wang , Zhaoshun Gao , Yanpeng Qi , Xianping Zhang , Dongliang Wang , Yanwei Ma

we were able to develop a novel method to synthesize Fe-based oxypnictide superconductors. By using LnAs and FeO as the starting materials and a ball-milling process prior to solid-state sintering, Tc as high as 50.7 K was obtained with the…

Superconductivity · Physics 2010-04-08 Ai-Hua Fang , Fu-Qiang Huang , Xiao-Ming Xie , Mian-Heng Jiang

The electronic phase diagram of PrFeAsO$_{1-x}$F$_{x}$ (0$\leq$x$\leq$0.225) has been determined using synchrotron X-ray powder diffraction, magnetization and resistivity measurements. The structural transition temperature is suppressed…

Bulk polycrystalline Ni-substituted SmFe1-xNixAsO (x = 0.0 to 1.0) samples are synthesized by solid state reaction route in an evacuated sealed quartz tube. The cell volume decreases with increase of Ni content in SmFe1-xNixAsO, thus…

Superconductivity · Physics 2015-06-11 Anand Pal , S. S. Mehdi , Mushahid Husain , V. P. S. Awana

We demonstrate buffer-gas cooling, high-resolution spectroscopy and cycling fluorescence of cold barium monofluoride (BaF) molecules. Our source produces an intense and internally cold molecular beam containing the different BaF…

Atomic Physics · Physics 2020-01-13 Ralf Albrecht , Michael Scharwaechter , Tobias Sixt , Lucas Hofer , Tim Langen

Ceramic $BiFeO_{3}$ samples were prepared by rapid sintering at $880^OC$. Two compositions were examined. A $56/44\ Bi_{2}O_{3}/Fe_{2}O_{3}\ mole\%$ composition and a $56Bi_{2}O_{3}\cdot44Fe_{2}O_{3}+6.5wt\%\,NaCl$ composition. The samples…

Materials Science · Physics 2021-06-28 Gilad Orr , Andrey Goryachev , Gady Golan

We report measurements of the phonon density of states as measured with inelastic x-ray scattering in SmFeAsO$_{1-x}$F$_y$ powders. An unexpected strong renormalization of phonon branches around 23 meV is observed as fluorine is substituted…

We report a systematic study by 75As nuclear-quadrupole resonance in LaFeAsO1-xFx. The antiferromagnetic spin fluctuation (AFSF) found above the magnetic ordering temperature TN = 58 K for x = 0.03 persists in the regime 0.04 < x < 0.08…

Superconductivity · Physics 2015-05-28 T. Oka , Z. Li , S. Kawasaki , G. F. Chen , N. L. Wang , Guo-qing Zheng

A suppression of superconductivity in the late rare earth RFeAsO1-xFx materials is reported. The maximum critical temperature (Tc) decreases from 51 K for R = Tb to 36 K for HoFeAsO0.9F0.1, which has been synthesised under 10 GPa pressure.…

Superconducting poly- and single-crystalline samples of Sm1-xThxFeAsO with partial substitution of Sm3+ by Th4+ were synthesized and grown under high pressure and their structural, magnetic and transport properties are studied. The…

Superconductivity · Physics 2011-05-25 N. D. Zhigadlo , S. Katrych , S. Weyeneth , R. Puzniak , P. Moll , Z. Bukowski , J. Karpinski , H. Keller , B. Batlogg

A series of layered CeO$_{1-x}$F$_x$FeAs compounds with x=0 to 0.20 are synthesized by solid state reaction method. Similar to the LaOFeAs, the pure CeOFeAs shows a strong resistivity anomaly near 145 K, which was ascribed to the…

Superconductivity · Physics 2008-06-20 G. F. Chen , Z. Li , D. Wu , G. Li , W. Z. Hu , J. Dong , P. Zheng , J. L. Luo , N. L. Wang