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Related papers: Study on the formation of MgB2 phase

200 papers

We report synthesis and superconductivity at 3.7K in PrO0.5F0.5BiS2. The newly discovered material belongs to the layered sulfide based REO0.5F0.5BiS2 compounds having ZrCuSiAs type structure. The bulk polycrystalline compound is…

Superconductivity · Physics 2013-03-08 Rajveer Jha , Anuj Kumar , Shiva Kumar Singh , V. P. S. Awana

A new route to the sintering of MgB2 has been identified, based on a reactive infiltration of liquid Mg on a powdered B preform. The technique allows to obtain large bulk manufacts in an inexpensive way, without the need of high pressure…

Superconductivity · Physics 2009-11-07 Giovanni Giunchi

A systematic study on the synthesis of the Ru-1212 compound by preparing a series of samples that were annealed at increasing temperatures and then quenched has been performed. It results that the optimal temperature for the annealing lies…

Superconductivity · Physics 2007-05-23 R. Masini , C. Artini , M. R. Cimberle , G. A. Costa , M. Carnasciali , M. Ferretti

We present electrical transport, magnetization, and specific heat measurements on bulk MgB2 samples (T_{c} = 38.5 K) synthesized under 200 MPa pressure using a process based on hot isostatic pressing with cooling under pressure. The samples…

Superconductivity · Physics 2009-11-07 N. A. Frederick , Shi Li , M. B. Maple , V. F. Nesterenko , S. S. Indrakanti

A commercial stainless steel tube was employed to synthesize MgB2. The specimen was prepared by a stoichiometric mixture of Mg and B. The specimen that had been enveloped in the commercial stainless steel tube was synthesized for 2 hours at…

Superconductivity · Physics 2007-05-23 H. B. Lee , Y. C. Kim , B. J. Kim , D. Y. Jeong

We report the growth of high-quality c-axis-oriented epitaxial MgB2 thin films by using a pulsed laser deposition technique. The thin films grown on (1`1 0 2) Al2O3 substrates show a Tc of 39 K. The critical current density in zero field is…

Superconductivity · Physics 2009-11-07 W. N. Kang , Hyeong-Jin Kim , Eun-Mi Choi , C. U. Jung , Sung-Ik Lee

We demonstrate direct evidence of possible surface superconductivity on small, well-shaped MgB2 single crystals. Transport measurements in the range H < 1.6 Hc2^c, where Hc2^c is the bulk upper critical field for the c axis, show non-Ohmic…

The upper critical field Hc2(T) of sintered pellets of the recently discovered MgB_2 superconductor was investigated in magnetic fields up to 16 T. The upper critical field of the major fraction of the investigated sample was determined…

Superconductivity · Physics 2014-10-13 K. -H. Müller , G. Fuchs , A. Handstein , K. Nenkov , V. N. Narozhnyi , D. Eckert

We report on high-order harmonic generation in the two-band superconductor MgB$_2$ driven by intense terahertz electromagnetic pulses. Third- and fifth-order harmonics are resolved in time domain and investigated as a function of…

According to the crystal structure of MgB$_{2}$ and band structure calculations quasi-two-dimensional (2D) boron planes are responsible for the superconductivity. We report on critical fields and resistance measurements of 30 nm thick…

Superconductivity · Physics 2009-11-07 A. S. Sidorenko , L. R. Tagirov , A. N. Rossolenko , V. V. Ryazanov , R. Tidecks

The electronic anisotropy in MgB2, is still a not completely clear topic; high quality c-oriented films are suitable systems to investigate this property. In this work we present our results on MgB2 superconducting thin films grown on MgO…

Precise structural information on the Mg1-xAlxB2 superconductors in the vicinity of x 0.5 is derived from high-resolution synchrotron X-ray powder diffraction measurements. We find that a hexagonal superstructure, accompanied by doubling of…

Materials Science · Physics 2009-11-07 S. Margadonna , K. Prassides , I. Arvanitidis , M. Pissas , G. Papavassiliou , A. N. Fitch

A Hybrid Physical-Chemical Vapour Deposition (HPCVD) system consisting of separately controlled Mg-source heater and substrate heater is used to grow MgB2 thin films and thick films at various temperatures. We are able to grow…

Superconductivity · Physics 2011-12-20 K. Chen , M. Veldhorst , C. H. Lee , D. R. Lamborn , R. DeFrain , J. M. Redwing , Q. Li , X. X. Li

It is shown that the transition to the low temperature superconducting state in a 3D metal at high magnetic field is smeared dramatically by thermal fluctuation of the superconducting order parameter. The resulting superconducting-to-normal…

Superconductivity · Physics 2013-05-29 T. Maniv , V. Zhuravlev

Single crystals of MgB2 with a size up to 1.5x0.9x0.2 mm3 have been grown with a high pressure cubic anvil technique. The crystal growth process is very peculiar and involves an intermediate nitride, namely MgNB9. Single crystals of BN and…

We report a detailed study of the microstructure and defects in sintered polycrystalline MgB2. Both TEM and x-ray data reveal that MgO is the major second-phase in our bulk samples. Although MgB2 and MgO have different crystal symmetries,…

Superconductivity · Physics 2009-11-07 Y. Zhu , L. Wu , V. Volkov , Q. Li , G. Gu , A. R. Moodenbaugh , M. Malac , M. Suenaga , J. Tranquada

A ternary compound, MgPtSi, was synthesized by solid-state reaction. An examination of the compound by powder X-ray diffraction revealed that it crystallizes in the orthorhombic TiNiSi-type structure with the Pnma space group. The structure…

Superconductivity · Physics 2015-05-21 Kazutaka Kudo , Kazunori Fujimura , Seiichiro Onari , Hiromi Ota , Minoru Nohara

Powdered and sintered MgB2 samples have been characterized through magnetic measurements performed from T = 5 K up to few degrees above the transition temperature of about 39 K. We found that the sintered samples behave as well-connected…

Superconductivity · Physics 2009-11-07 M. R. Cimberle , M. Novak , P. Manfrinetti , A. Palenzona

Continued advances in superconducting qubit performance require more detailed understandings of the many sources of decoherence. Within these devices, two-level systems arise due to defects, interfaces, and grain boundaries, and are thought…

The discovery of superconductor in magnesium diboride MgB2 with high Tc (39 K) has raised some challenging issues; whether this new superconductor resembles a high temperature cuprate superconductor(HTS) or a low temperature metallic…

Superconductivity · Physics 2009-11-07 M. Xu , H. Kitazawa , Y. Takano , J. Ye , K. Nishida , H. Abe , A. Matsushita , G. Kido