Impurity scattering effects on the low-temperature specific heat ofd-wave superconductors

Abstract

Very recently impurity scattering effects on quasiparticles in d-wave superconductors have attracted much attention. Especially, the thermodynamic properties in magnetic fields H are of interest. We have measured the low-temperature specific heat C (T,H)

BCS-like superconductivity inMgCNi3

“…The results are represented by the dashed line in Fig.4(b). Apparently, the data can not be well described in this manner, in contrast to the nice δγ(H)∝H 1/2 relation found in cuprates[20][21][22][23][24]. A phenomenological fit of δC/T(H)∝H n leads to n=0.73 (the dot line in Fig.4(b)), similar to that in the dirty-limitY(Ni 1-y Pt y )B 2 C [34].Due to the proximity of ferromagnetism, superconducting order parameter in MgCNi 3 was expected to be p-wave by[3] and others.…”

“…4(b). Apparently, the data can not be well described in this manner, in contrast to the nice δγ(H)∝H 1/2 relation found in cuprates [20][21][22][23][24]. A phenomenological fit of δC/T(H)∝H n leads to n=0.73 (the dot line in Fig.…”

Order Parameter ofMgB2: A Fully Gapped Superconductor

“…If However, the electronic specific heat is better determined at low temperatures since at high temperatures a large phonon specific heat has to be subtracted. Details of the measurements and the system calibrations can be found in [5][6][7]. T [8], ∆C above 20 K can be obtained by…”

Phonon anomaly and anisotropic superconducting gap in non-centrosymmetric Li2(Pd1-xPtx)3B

“…For x = 0.84, γ res is even higher and the temperature dependence diminishes at low temperatures. It has been known that the temperature dependence of c el /T for T ≪ T c becomes weaker if impurity scatterings exist [21]. Thus, the observed overall tendency is most consistent with an anisotropic or nodal superconducting gap for x 0.5.…”