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J.G. Sereni, P. Pedrazzini, E. Bauer, A. Galatanu, Y. Aoki, H. Sato:
"Detailed study of the CePd_2-xNi_xAl₃ magnetic phase diagram around its critical concentration";
Journal of Physics: Condensed Matter, 18 (2006), S. 3789 - 3802.

Detailed study of the CePd_2-xNi_xAl₃ magnetic phase diagram around its critical concentration

J G Sereni 1, P Pedrazzini 2, E Bauer 3, A Galatanu 4, Y Aoki 5 and H Sato 5
1 Lab. Bajas Temperaturas, Centro Atómico Bariloche (CNEA) and CONICET, RA-8400 S.C. de Bariloche, Argentina
2 DPMC-Universitè de Genève, Q. E.-Ansermet, CH-1211 Genève, Switzerland
3 Institut für Festkörperphysik, Technische Universität Wien, A-1040 Wien, Austria
4 National Institute for Material Physics, Atomistilor 105 bis, Bucharest-Magurele, POB MG-07, 077125, Romania
5 Department of Physics, Tokyo Metropolitan University, Minami-Ohsawa 1-1, Hachioji-Shi, Tokyo 192-0397, Japan
E-mail: jsereni@cab.cnea.gov.ar

Abstract:
Thermal, magnetic and transport measurements on CePd_2-xNi_xAl₃ alloys within the 0<=x<=1 range are reported, including applied pressure (p) and magnetic field on some selected samples. The low temperature results indicate that long range antiferromagnetic order is robust up to x = 0.2, whereas between 0.25 and 0.5 magnetic fluctuations give rise to non-Fermi-liquid (NFL) behaviour. In this critical region, the low temperature specific heat can be described as due to two components, the major showing a NFL C_p/T=γ₀ - γ₁ sqrt{T} dependence, while the minor one includes a decreasing fraction of short range order degrees of freedom. The latter is only observed close to the critical point, x_cr~0.35. Electrical resistivity ρ studies performed under pressure for x = 0.5 allow us to investigate the evolution of the NFL state around and beyond x_cr, where the exponent of ρ α Tⁿ increases from n = 1 (for p = 0) up to n = 2 (for p = 12 kbar). This exponent is also observed at normal pressure on the x = 1.0 sample, indicating the onset of the Fermi liquid behaviour. Doping and pressure effects are compared by fitting high temperature resistivity data employing a unique function which allows us to describe the evolution of the characteristic energy of this series along a large range of concentration and pressure.

Print publication: Issue 15 (19 April 2006)
Received 14 December 2005, in final form 5 March 2006
Published 30 March 2006

http://aleph.ub.tuwien.ac.at/F?base=tuw01&func=find-c&ccl_term=AC06588055

http://dx.doi.org/10.1088/0953-8984/18/15/022