TY - JOUR
T1 - Specific heat, susceptibility, magnetotransport and thermoelectric power of the Kondo alloys (Ce1-xLax)Cu5In
AU - Tchoula Tchokonté, M. B.
AU - De V Du Plessis, P.
AU - Strydom, A. M.
AU - Kaczorowski, D.
AU - Czopnik, A.
AU - Kletowski, Z.
PY - 2004/3/31
Y1 - 2004/3/31
N2 - The influence of substituting Ce with La in the Kondo compound CeCu5In has been investigated using x-ray diffraction, specific heat (Cp), electrical resistivity (ρ(T)), magnetoresistivity (MR) and thermoelectric power (TEP) measurements. Cp of CeCu5In and the (Ce1-xLax)Cu5In alloys shows enhanced values at low temperatures. Between 10 and 20 K the equation Cp/T = γconv + βT2 fits the data for all alloys with γconv scaling linearly with Ce concentration. Below 10 K a pronounced upturn in Cp values occurs. Susceptibility data above 100 K follow the Curie-Weiss relation and give effective moment μeff values in fair agreement with that of a Ce3+-ion. The ρ(T) studies illustrate the evolution from Kondo lattice to single-ion Kondo behaviour with increase in La content in the (Ce1-xLax)Cu5In alloy series. MR measurements on Ce dilute alloys are interpreted within the single-ion Bethe ansatz description and values of the Kondo temperature TK are calculated. A compressible Kondo lattice model has been used to describe the decrease in TK and in Tmρ (the temperature at which a maximum in ρ(T) occurs for the coherent dense Kondo alloys) with decrease in Ce concentration for these alloys. The TEP is positive and shows a maximum at approximately 45 K for several investigated (Ce1-xLax)Cu5In alloys.
AB - The influence of substituting Ce with La in the Kondo compound CeCu5In has been investigated using x-ray diffraction, specific heat (Cp), electrical resistivity (ρ(T)), magnetoresistivity (MR) and thermoelectric power (TEP) measurements. Cp of CeCu5In and the (Ce1-xLax)Cu5In alloys shows enhanced values at low temperatures. Between 10 and 20 K the equation Cp/T = γconv + βT2 fits the data for all alloys with γconv scaling linearly with Ce concentration. Below 10 K a pronounced upturn in Cp values occurs. Susceptibility data above 100 K follow the Curie-Weiss relation and give effective moment μeff values in fair agreement with that of a Ce3+-ion. The ρ(T) studies illustrate the evolution from Kondo lattice to single-ion Kondo behaviour with increase in La content in the (Ce1-xLax)Cu5In alloy series. MR measurements on Ce dilute alloys are interpreted within the single-ion Bethe ansatz description and values of the Kondo temperature TK are calculated. A compressible Kondo lattice model has been used to describe the decrease in TK and in Tmρ (the temperature at which a maximum in ρ(T) occurs for the coherent dense Kondo alloys) with decrease in Ce concentration for these alloys. The TEP is positive and shows a maximum at approximately 45 K for several investigated (Ce1-xLax)Cu5In alloys.
UR - http://www.scopus.com/inward/record.url?scp=1842759800&partnerID=8YFLogxK
U2 - 10.1088/0953-8984/16/12/007
DO - 10.1088/0953-8984/16/12/007
M3 - Article
AN - SCOPUS:1842759800
SN - 0953-8984
VL - 16
SP - 1981
EP - 1994
JO - Journal of Physics Condensed Matter
JF - Journal of Physics Condensed Matter
IS - 12
ER -