Role of d-wave pairing in A15A15 superconductors

We argue that the recent Raman spectroscopy observation of a sharp mode in s-wave superconducting V$_3$Si is due to a competing d-wave pairing state. We present microscopic arguments for the origin of this d-wave order. We further argue that the d-wave order explains the observed shrinking of the vortex core structure at anomalously low magnetic fields and the large anisotropy observed in the upper critical field

mu. SR investigation of magnetism and superconductivity in (Y sub 1-x Pr sub x )Ba sub 2 Cu sub 3 O sub 7

Muon spin rotation and relaxation techniques have been used to study the superconductivity and magnetism in (Y{sub 1-x}Pr{sub x})Ba{sub 2}Cu{sub 3}O{sub 7} (0{le}x{le}1) and PrBa{sub 2}Cu{sub 3}O{sub 6}. Clear evidence for magnetic ordering of the Cu moments within the Cu-O planes is seen. Additionally, a lower magnetic transition is observed which, based upon previous work, has been associated with the ordering of Pr moments on the Y sublattice of the YBa{sub 2}Cu{sub 3}O{sub 7} structure. For x = 1, the upper Neel temperature T{sub N1} is {approximately}270 K and the magnitude of the fully developed local magnetic field is {approximately}16 mT. Below the lower Neel temperature T{sub N2} = 17 K, the magnitude of the static field is reduced to {approximately}12 mT. For 0.4{le}x{le}0.54, there appears to be a coexistence region of long-range magnetism and superconductivity. 4 refs., 5 figs