173 research outputs found
Superconductivity in BiS2-Based Layered Compounds
Crystal structure and physical properties of the novel BiS2-based layered
superconductors are briefly reviewed. Superconductivity in the BiS2-based
layered compounds is induced by electron doping into the BiS2 conduction
layers. The superconducting properties seem to correlate with the crystal
structure. Possible strategies for increasing transition temperature in this
family are discussed.Comment: 5 pages, 3 figures, a brief review submitted to ISS2013 proceeding
Nonvolatile Magneto-Thermal Switching in MgB2
Ongoing research explores thermal switching materials to control heat flow.
Specifically, there has been interest in magneto-thermal switching (MTS)
materials based on superconductors, which only exhibited switching behavior
when a magnetic field was applied. However, a recent report highlighted
nonvolatile MTS in commercial Sn-Pb solders, attributed to magnetic flux
trapping. In this study, we focused on flux trapping in a type-II
superconductor MgB2. Magnetization and thermal conductivity measurements under
magnetic fields were conducted on polycrystalline MgB2. We confirmed that
magnetic flux was indeed trapped in MgB2 even after demagnetization.
Additionally, we observed nonvolatile MTS in MgB2 as well as Sn-Pb solders.
These results suggest that the nonvolatile MTS may be a widespread
characteristic of superconducting materials with flux trapping.Comment: 10 pages, 4 figure
Evolution of two-step structural phase transition in Fe1+dTe detected by low-temperature x-ray diffraction
The low-temperature crystal structure of Fe1.13Te, which exhibits an
anomalous two-step magnetic transition, was clarified by the systematic x-ray
diffraction measurements. It was found that two-step structural phase
transition, tetragonal-orthorhombic-monoclinic, occurred correspondingly to the
two-step magnetic transition. The detailed analysis of the profile at 5 K
indicated the coexistence of the minor orthorhombic area inside the major
monoclinic lattice, which could explain the lower-shift (suppression) of the
antiferromagnetic transition temperature in Fe1.13Te and suggest a possibility
of superconductivity at the domain boundary.Comment: 12 pages, 3 figure
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