English
Related papers

Related papers: Study of superconducting properties of MgB2

200 papers

In-plane electrical transport properties of MgB2 single crystals grown under high pressure of 4-6 GPa and temperature of 1400-1700oC in Mg-B-N system have been measured. For all specimens we found sharp superconducting transition around…

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

Heat-capacity measurements of a 39 microgramm MgB_2 single crystal in fields up to 14 T and below 3 K allow the determination of the low-temperature linear term of the specific heat, its field dependence and its anisotropy. Our results are…

Superconductivity · Physics 2009-11-07 F. Bouquet , Y. Wang , I. Sheikin , T. Plackowski , A. Junod , S. Lee , S. Tajima

The superconducting phase diagram of MgB2 was determined from magnetization, magneto-transport and the first single-crystal specific heat measurements. A zero-temperature in-plane coherence length of 8 nm is determined. The superconducting…

The specific heat C of a sintered polycrystalline sample of MgB2 with a bulk superconducting transition temperature Tc=36.7 K is measured as a function of the temperature (2-300 K) and magnetic field (0-16 T), together with magnetic…

Superconductivity · Physics 2009-11-07 Y. Wang , T. Plackowski , A. Junod

We report on study of the electronic anisotropy of the newly discovered MgB2 superconductor using the in-plane resistivity measurements in magnetic field applied perpendicular and parallel to Mg and B planes of MgB2 single crystals. The…

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

We characterize the superconducting state of phase pure polycrystalline samples of the new layered superconductor MgB$_2$ by specific heat measurements in magnetic fields up to 9 T. The characteristic jump at the superconducting transition…

Superconductivity · Physics 2007-05-23 R. K. Kremer , B. J. Gibson , K. Ahn

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

The recently discovered superconductivity in MgB2 has created the world sensation. In spite of the relatively high superconducting transition temperature Tc=39K, the superconductivity is understood in terms of rare two gap superconductor…

Superconductivity · Physics 2007-05-23 T. Dahm , A. I. Posazhennikova , K. Maki

The heat capacity of a 2H-NbS2 single crystal has been measured by a highly sensitive ac technique down to 0.6 K and in magnetic fields up to 14 T. At very low temperatures data show excitations over an energy gap (2DS/kBTc \approx 2.1)…

Superconductivity · Physics 2015-05-20 J. Kacmarcik , Z. Pribulova , C. Marcenat , T. Klein , P. Rodiere , L. Cario , P. Samuely

Far-infrared reflectivity studies on the polycrystalline intermetallic compound MgB_2 with a superconducting transition temperature T_c=39 K were performed at temperatures 20 K to 300 K. We observe a significant raise of the…

The review considers bulk MgB2-based materials in terms of their structure, superconducting and mechanical properties. Superconducting transition temperatures of 34.5-39.4 K, critical current densities of 1.8-1.0 x E6 A/sq.cm in self field…

Superconductivity · Physics 2009-12-25 T. A. Prikhna

The specific heat of two polycrystalline samples of MgB_2 is presented and analyzed (2 - 300 K, 0 - 16 T), together with magnetic properties. The main characteristics are a low density of states at the Fermi level, high phonon frequencies,…

Superconductivity · Physics 2007-05-23 Alain Junod , Yuxing Wang , Frederic Bouquet , Pierre Toulemonde

Polarisation-resolved Raman scattering measurements were performed on MgB_2 single crystals to determine the magnitude, symmetry and temperature dependence of the superconducting gap. A single sharp peak due to Cooper pair breaking appears…

Superconductivity · Physics 2007-05-23 J. W. Quilty , S. Lee , A. Yamamoto , S. Tajima

The two-gap structure in the superconducting state of MgB_2 gives rise to unusual thermodynamic properties which depart markedly from the isotropic single-band BCS model, both in their temperature- and field dependence. We report and…

Superconductivity · Physics 2009-11-07 F. Bouquet , Y. Wang , I. Sheikin , P. Toulemonde , M. Eisterer , H. W. Weber , S. Lee , S. Tajima , A. Junod

This paper reports specific-heat measurements on superconducting MgB2 in magnetic fields to 9 T. In zero magnetic field the data can be fitted to a two-gap model, which is a generalization of a semi-empirical model for strong-coupled,…

Superconductivity · Physics 2007-05-23 R. A. Fisher , F. Bouquet , N. E. Phillips , D. G. Hinks , J. D. Jorgensen

We report on measurements of the magnetic moment in superconducting MgB2 single crystals. We find \mu_0H_{c2}^c(0) = 3.2 T, \mu_0H_{c2}^{ab}(0) = 14.5 T, \gamma = 4.6, \mu_0H_c(0) = 0.28 T, and \kappa(T_c) = 4.7. The standard…

Superconductivity · Physics 2009-11-07 M. Zehetmayer , M. Eisterer , H. W. Weber , J. Jun , S. M. Kazakov , J. Karpinski , A. Wisniewski

The recently discovered superconductivity in MgB2 has captured world attention due to its simple crystal structure and relatively high superconducting transition temperature Tc=39K. It appears to be generally accepted that it is…

Superconductivity · Physics 2009-11-07 A. I. Posazhennikova , T. Dahm , K. Maki

We studied the effect of disorder on the superconducting properties of polycrystalline MgB_2 by specific-heat measurements. In the pristine state, these measurements give a bulk confirmation of the presence of two superconducting gaps with…

Here we report the growth of sub-millimeter MgB2 single crystals of various shapes under high pressure in Mg-B-N system. Structure refinement using a single-crystal X-ray diffraction analysis gives lattice parameters a=3.0851(5) A and…

Superconductivity · Physics 2009-11-07 S. Lee , H. Mori , T. Masui , Yu. Eltsev , A. Yamamoto , S. Tajima

The specific heat of polycrystalline Mg$^{11}$B$_{2}$ has been measured with high resolution ac calorimetry from 5 to 45 K at constant magnetic fields. The excess specific heat above T$_{c}$ is discussed in terms of Gaussian fluctuations…

Superconductivity · Physics 2009-11-07 Tuson Park , M. B. Salamon , C. U. Jung , Min-Seok Park , Kyunghee Kim , Sung-Ik Lee
‹ Prev 1 2 3 10 Next ›