S. Yadam; Durgesh Singh; D. Venkateshwarlu; M. Gangrade; S. S. Samatham; V. Ganesan
Abstract
CeNi2Al3 system is a potential candidate for low temperature thermoelectrics. Substitution studies, especially at the Ni site are considered to be of importance due to the drastic tuning of its physical properties. Resistivity in magnetic fields and thermoelectric power measurements of Cu doped CeNi2Al3 ...
Read More
CeNi2Al3 system is a potential candidate for low temperature thermoelectrics. Substitution studies, especially at the Ni site are considered to be of importance due to the drastic tuning of its physical properties. Resistivity in magnetic fields and thermoelectric power measurements of Cu doped CeNi2Al3 (x=0.0 to 0.4) system is reported in this investigation. This dense Kondo lattice system is investigated with an aim of understanding its basic transport mechanism. Negative magnetoresistance is seen for x=0.3 and 0.4 in the magnetic field up to 14 T. Deviation from the Kondo behavior occurs at temperatures close to 2 K with a down turn in resistivity. The nature of resistivity at low temperatures is investigated in view of the possible evidence for Fermi liquid behavior and also the formation of heavy Fermion in corroboration with specific heat studies. Doping dependence of linear diffusion coefficient and Sommerfeld coefficient of specific heat are analyzed and discussed in connection with the heavy Fermion formation. The results obtained show a promising trend in tuning these materials by way of Kondo route as well as by the substitution especially at the Ni site in the present system.
M.A. AL-Jalali
Abstract
The S-d exchange interactions in dilute Cu-Mn alloys was studied on concentration (C) varying between 10.5 and 2081.8 ppm of Mn in Cu within the (0.03K–4.2K) temperature range. Using electrical resistivity data on those alloys, the s-d exchange integral (Jsd), which is negative, has calculated ...
Read More
The S-d exchange interactions in dilute Cu-Mn alloys was studied on concentration (C) varying between 10.5 and 2081.8 ppm of Mn in Cu within the (0.03K–4.2K) temperature range. Using electrical resistivity data on those alloys, the s-d exchange integral (Jsd), which is negative, has calculated to show a clear dependence on (Ln C). This dependence, confirming thus the dominance of Kondo effect below 1000 ppm impurity concentration, but above this concentration, we expected an interference between Kondo effect and spin glass regime, which mean that spin glass regime has to prevail more than Kondo effect.
