Related papers: Properties of MgB2 bulk
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…
Nanocrystalline MgB$_2$ produced by mechanical alloying has been shown to exhibit enhanced superconducting properties such as increased pinning and higher critical currents. However, the effects of the synthesis process on the intrinsic…
Bulk samples of MgB2 have been formed by hot isostatic pressing (HIPping) of commercial powder at 100MPa and 950=B0C. The resulting material is 100% dense with a sharp superconducting transition at 37.5K. Microstructural studies have…
Seven years after the discovery of superconductivity in magnesium diboride, the fundamental superconducting properties of this compound are well known and the peculiar current transport in polycrystalline materials is essentially…
The discovery of superconductivity at 39 K in magnesium diboride offers the possibility of a new class of low-cost, high-performance superconducting materials for magnets and electronic applications. With twice the critical temperature of…
We discuss the important aspects of synthesis and crystal growth of MgB2 under high pressure (P) and temperature (T) in Mg-B-N system, including the optimisation of P-T conditions for reproducible crystal growth, the role of liquid phases…
The normal state and superconducting properties of MgB2 and Mg1-xAlxB2 are discussed based on structural, transport, and high pressure experiments. The positive Seebeck coefficient and its linear temperature dependence for Tc<T<160 K…
The fabrication, characterisation, and superconductivity of MgB2 thick films grown on stainless steel substrate were studied. XRD, SEM, and magnetic measurements were carried out. It was found that the MgB2 thick films can be fast formed by…
The structural properties of MgB2 superconductors have been analyzed by means of convergent-beam electron diffraction, high-resolution transmission-electron microscopy, and theoretical simulations. The MgB2 crystal has been identified to…
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…
Superconducting properties of bulk, dense, pure MgB2 and doped (Mg1-xAx)B2 samples with A = Na, Ca, Cu, Ag, Zn and Al were studied for compositional ranges 0 < x < 0.20. The effect on pinning properties and critical current were…
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 basic magnetic and electronic properties of most binary compounds have been well known for decades. Therefore the recent announcement of superconductivity at 39 K in the simple binary ceramic compound MgB2 is surprising. This compound,…
Solid MgB$_2$ has rather interesting and technologically important properties, such as a very high superconducting transition temperature. Focusing on this compound, we report the first non-trivial application of a novel…
Thin films of MgB2 superconductor were prepared by three different procedures on sapphire and silicon substrates. Boron thin films, ex-situ annealed in magnesium vapour, resulted in textured polycrystalline films with crystal dimensions…
Recently it was discovered that, under elevated pressures, MoB$_2$ exhibits superconductivity at a critical temperature, $T_c$, as high as 32 K. The superconductivity appears to develop following a pressure-induced structural transition…
A polycrystalline sample of the MgB_2 superconductor was investigated by measurements of the electrical resistivity, the thermopower and the thermal conductivity in the temperature range between 1.8K and 300K in zero magnetic field. The…
Materials of the Y-Ba-Cu-O (melt-textured YBa2Cu3O7-d-based materials or MT-YBCO) and Mg-B-O (MgB2-based materials) systems with high superconducting performance, which can be attained due to the formation of regularly distributed…
Dense pure and doped (Mg1-xAx)B2 samples with A = Na, Ca, Cu, Ag, Zn and Al were synthesized at high pressure - high temperature in a multi anvils press (3.5-6 GPa, 900-1000C) for x up to 0.20. They were studied by x-ray diffraction,…
Electrolysis was carried out on fused mixtures of MgCl2, NaCl, KCl and MgB2O4 under an Ar flow at 600C. Electrical resistivity measurements for the grown deposits show an onset of superconducting transition at 37 K in the absence of applied…