11,590 research outputs found
Electronic transport properties of intermediately coupled superconductors: PdTe2 and Cu0.04PdTe2
We have investigated the electrical resistivity, Seebeck coefficient and
thermal conductivity of PdTe2 and 4% Cu intercalated PdTe2 compounds.
Electrical resistivity for the compounds shows Bloch-Gruneisen type linear
temperature (T) dependence for 100 K < T < 480 K, and Fermi liquid behavior (~
T^2) below 50 K. Seebeck coefficient data exhibit strong competition between
Normal (N) and Umklapp (U) scattering processes at low T. Though our results
indicate the transfer of charge carriers to PdTe2 upon Cu intercalation, it is
difficult to discern any change in the Fermi surface of the compound by
Nordheim-Gorter plots. The estimated Fermi energies of the compounds are quite
comparable to good metals Cu, Ag and Au. The low T, thermal conductivity (k) of
the compounds is strongly dominated by the electronic contribution, and
exhibits a rare linear T dependence below 10 K. However, high T, k(T) shows
usual 1/T dependence, dominated by U scattering process. The electron phonon
coupling parameters, estimated from the low T, specific heat data and first
principle electronic structure calculations suggest that PdTe2 and Cu0.04PdTe2
are intermediately coupled superconductors.Comment: 18 pages, 6 figure
Superconductivity at 5.2 K in ZrTe3 polycrystals and the effect of Cu, Ag intercalation
We report the occurrence of superconductivity in polycrystalline samples of
ZrTe3 at 5.2 K temperature at ambient pressure. The superconducting state
coexists with the charge density wave (CDW) phase, which sets in at 63K. The
intercalation of Cu or Ag, does not have any bearing on the superconducting
transition temperature but suppresses the CDW state. The feature of CDW anomaly
in these compounds is clearly seen in the DC magnetization data. Resistivity
data is analysed to estimate the relative loss of carriers and reduction in the
nested Fermi surface area upon CDW formation in the ZrTe3 and the intercalated
compounds.Comment: 5 pages, 8 figure
Dark sector interaction: a remedy of the tensions between CMB and LSS data
The well-known tensions on the cosmological parameters and
within the CDM cosmology shown by the Planck-CMB and LSS data are
possibly due to the systematics in the data or our ignorance of some new
physics beyond the CDM model. In this letter, we focus on the second
possibility, and investigate a minimal extension of the CDM model by
allowing a coupling between its dark sector components (dark energy and dark
matter). We analyze this scenario with Planck-CMB, KiDS and HST data, and find
that the and tensions disappear at 68\% CL. In the joint
analyzes with Planck, HST and KiDS data, we find non-zero coupling in the dark
sector up to 99\% CL. Thus, we find a strong statistical support from the
observational data for an interaction in the dark sector of the Universe while
solving the and tensions simultaneously.Comment: 5 pages, 3 figure
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