English
Related papers

Related papers: Influence of Mg deficiency in MgB2 single crystals…

200 papers

We present a Raman scattering study of the E2g phonon anharmonicity and of superconductivity induced self-energy effects in MgB2 single crystals. We show that anharmonic two phonon decay is mainly responsible for the unusually large…

Superconductivity · Physics 2009-11-13 A. Mialitsin , B. S. Dennis , N. D. Zhigadlo , J. Karpinski , G. Blumberg

Superconducting magnesium diboride films with Tc0 ~ 24 K and sharp transition \~ 1 K were successfully prepared on silicon substrates by pulsed laser deposition from a stoichiometric MgB2 target. Contrary to previous reports, anneals at 630…

Superconductivity · Physics 2009-11-07 H. Y. Zhai , H. M. Christen , L. Zhang , C. Cantoni , M. Paranthaman , B. C. Sales , D. K. Christen , D. H. Lowndes

Superconducting (SC) gap symmetry and magnetic response of cubic U0.97Th0.03Be13 are studied by means of high-precision heat-capacity and dc magnetization measurements using a single crystal, in order to address the long-standing question…

We report resistivity and the Hall effect measurements in the normal and superconducting states of MgB2 single crystal. The resistivity has been found to be anisotropic with slightly temperature dependent resistivity ratio of about 3.5. The…

Superconductivity · Physics 2009-11-07 Yu. Eltsev , K. Nakao , S. Lee , T. Masui , N. Chikumoto , S. Tajima , N. Koshizuka , M. Murakami

"F-free" CeOBiS$_2$ single crystals have successfully grown, thoroughly eliminating a concern about F-contamination by using a high-purity CsCl flux. The obtained crystals have a plate-like shape with a size of 1.0-3.0 mm in the…

The hydrostatic pressure effect on the newly discovered superconductor MgB2 has been determined. The transition temperature Tc was found to decrease linearly at a large rate of -1.6 K/GPa, in good quantitative agreement with the ensuing…

Superconductivity · Physics 2009-11-07 B. Lorenz , R. L. Meng , C. W. Chu

The phenomenally large enhancement in conductivity observed when Li-doped MgO crystals are oxidized at elevated temperatures was investigated by dc and ac electrical measurements in the temperature interval 250-673 K. The concentration of…

Materials Science · Physics 2009-11-07 M. M. Tardio , R. Ramirez , R. Gonzalez , Y. Chen

The thermal expansion of polycrystalline MgB2 from 5-300 K is studied using high-resolution capacitance dilatometry. The thermal expansivity exhibits a small jump of -5.8x10-8 K-1 at Tc (in accord with expectations from the Ehrenfest…

Superconductivity · Physics 2007-05-23 R. Lortz , C. Meingast , D. Ernst , B. Renker , D. D. Lawrie , J. P. Franck

Superconductivity has been explored in single crystals of the Ni-doped FeAs-compound SrFe2-xNixAs2 grown by self-flux solution method. The antiferromagnetic order associated with the magnetostructural transition of the parent compound…

Superconductivity · Physics 2011-01-27 Shanta R. Saha , Nicholas P. Butch , Kevin Kirshenbaum , Johnpierre Paglione

Case studies of $1T$-TiSe$_2$ and YBa$_2$Cu$_3$O$_{7-\delta}$ have demonstrated that x-ray diffraction (XRD) studies can be used to trace even subtle structural phase transitions which are inherently connected with the onset of…

Aliovalent rare earth substitution into the alkaline earth site of CaFe2As2 single-crystals is used to fine-tune structural, magnetic and electronic properties of this iron-based superconducting system. Neutron and single crystal x-ray…

Superconductivity · Physics 2015-03-19 S. R. Saha , N. P. Butch , T. Drye , J. Magill , S. Ziemak , K. Kirshenbaum , P. Y. Zavalij , J. W. Lynn , J. Paglione

Single crystalline FeTe$_{0.61}$Se$_{0.39}$ with a sharp superconducting transition at $T_{\textrm{c}} \sim$ 14 K is synthesized via slow furnace cooling followed by low-temperature annealing. The effect of annealing on the chemical and…

Superconductivity · Physics 2015-05-13 T. Taen , Y. Tsuchiya , Y. Nakajima , T. Tamegai

AgSbTe2 is a well-known thermoelectric material with a high Seebeck coefficient and intrinsically low thermal conductivity, but its behavior under pressure remains largely unexplored. Here we report a systematic investigation of the…

Density functional calculations are used to investigate the effects of partial substitutional alloying of the B site in MgB2 with C and Be alone and combined with alloying of the Mg site with Cu. The effect of such substitutions on the…

Superconductivity · Physics 2009-11-07 M. J. Mehl , D. A. Papaconstantopoulos , D. J. Singh

Bismuth displays puzzling superconducting properties. In its crystalline equilibrium phase, it does not seem to superconduct at accessible low temperatures. However, in the amorphous phase it displays superconductivity at ~ 6 K. Under…

We performed ac-susceptibility measurements of magnesium diboride powder samples under pure hydrostatic pressures up to 0.4 GPa and under quasi-hydrostatic pressure conditions up to 8 GPa in a helium gas pressure cell and a diamond-anvil…

Superconductivity · Physics 2007-05-23 S. I. Schlachter , W. H. Fietz , K. Grube , W. Goldacker

High-quality superconducting KxFeySe2 single crystals were synthesized using an easy one-step method. Detailed annealing studies were performed to make clear the phase formation process in KxFeySe2. Compatible observations were found in…

Superconductivity · Physics 2015-06-18 W. Zhou , X. Li , X. Zhou , F. F. Yuan , Y. Ding , J. C. Zhuang , Y. Sun , H. L. Zhou , Z. X. Shi

The influence of room-temperature annealing on the parameters of the basal-plane electrical resistance of underdoped YBa$_2$Cu$_3$O$_{7-\delta}$ and HoBa$_2$Cu$_3$O$_{7-\delta}$ single crystals in the normal and superconducting states is…

Superconductivity · Physics 2019-01-21 R. V. Vovk , G. Ya. Khadzhai , Z. F. Nazyrov , S. N. Kamchatnaya , O. V. Dobrovolskiy

We report a high-pressure study of simultaneous low-temperature electrical resistivity and Hall effect measurements on high quality single-crystalline KFe2As2 using designer diamond anvil cell techniques with applied pressures up to 33 GPa.…

Specific heat has been measured down to 600 mK and up to 8 Tesla by the highly sensitive AC microcalorimetry on the MgCNi3 single crystals with Tc ~ 7 K. Exponential decay of the electronic specific heat at low temperatures proved that a…