相关论文: Permanent magnet with MgB2 bulk superconductor
Superconducting bulk properties of ternary Nb2 BN are confirmed and are described by means of magnetization, electronic transport and specific-heat measurements. BCS conventional super- conductivity is found with Tc = 4.4 K. Critical fields…
Magnetic ions (Mn) were substituted in MgB_2 single crystals resulting in a strong pair-breaking effect. The superconducting transition temperature, T_c, in Mg_{1-x}Mn_xB_2 has been found to be rapidly suppressed at an initial rate of 10…
The bulk upper critical field H_{c2}(T) of superconducting MgB_2 and its anisotropy are established by analyzing experimental data on the temperature and magnetic field dependences of the ab-plane thermal conductivity of a…
Enhancing the critical temperature (TC) is important not only to the practical applications but also to the theories of superconductivity. MgB2 is a type II superconductor with a TC of 39 K, which is very close to the McMillan limit.…
High-temperature superconductors (HTS) could enable high-field magnets much stronger than is possible with Nb-Ti and Nb3Sn, but two key limiting factors have so far been the difficulty of achieving high critical current density in…
The investigation of transport characteristics in high-temperature superconductors under magnetic fields is one of the most important topics in condensed matter physics and transport applications. For YBa$_2$Cu$_3$O$_7$ (YBCO), the…
We report variation of lattice structure in diborides (AB2) with different A atoms to identify the special case of MgB2 showing high Tc superconductivity. High purity MgB2 (Tc~39 K) has been prepared by direct reaction of the elements and…
The extremely large transverse magnetoreistance (the magnetoresistant ratio $\sim 1.3\times10^5\%$ in 2 K and 9 T field, and $4.3\times 10^6\%$ in 0.4 K and 32 T field, without saturation), and the metal-semiconductor crossover induced by…
We synthesized single crystalline and policrystalline MgB_2 under ambient pressures. The single crystals of MgB_2 were of good quality, where the crystal structure refinements were successfully converged with R = 0.020. The specific heat of…
We report the large linear magnetoresistance ($\sim 300\%$ in 9 T field at 2 K) and magnetothermopower in layered SrZnSb$_2$ crystal with quasi-two-dimensional Sb layers. A crossover from the semiclassical parabolic field dependent…
A MgB2 superconducting tape has been successfully prepared by a new way of boron diffusion into Mg tape. This tape superconductor has a Tc of 39 K with a sharp transition width of 0.4 K, high bulk critical current density jc of 6.7*10^5…
Hard magnets with high coercivity, such as Nd2Fe14B and SmCo5 alloys, can maintain magnetisation under a high reverse external magnetic field and have therefore become irreplaceable parts in many practical applications. Molecular magnets…
In the search for MgB2-like phonon-mediated superconductors we have carried out a systematic density functional theory study of the Ca-B system, isoelectronic to Mg-B, at ambient and gigapascal pressures. A remarkable variety of candidate…
Bulk polycrystalline HgBa(2)Ca(2)Cu(3)O(x) materials were irradiated with 0.8 GeV protons to form randomly oriented columnar defects, by induced fission of Hg-nuclei. Proton fluences from 0 to 35 times 10^{16} cm^{-2} were used to install…
HTS has the potential of a game changer for many applications of superconductivity, not last in the field of particle accelerators and detectors. This paper explores the potential of HTS, with a focus on REBCO-coated conductors, in relation…
The microstructure of the MgB2 superconductor sintered at high temperature under a high pressure of about 3 GPa was investigated by using a high-resolution transmission electron microscope (HRTEM). The TEM images did not show any pores in…
Heterogeneous magnetic superconducting systems (HMSS) represent a new class of nanostructures. They are made of ferromagnetic (FM) and superconducting (SC) pieces separated by thin layers of insulating oxides. In contrast to the case of a…
The electrical resistivity $\rho$ and upper critical field $H_{c2}$ were measured in MgB$_2$ disordered by nuclear reactor neutrons. We found that superconducting temperature $T_c$ decreases under irradiation from 40 to 5 K. Despite strong…
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…
Magnesium diboride MgB2 has been an extraordinarily hot research topic since the discovery of superconductivity below 40 K, due to the vast amount of unusual properties originating from the involvement in superconductivity of two sets of…