Magnetic, thermal, and transport properties of single crystals of antiferromagnetic Kondo-latticeCe2PdSi3

Abstract

Magnetization, heat capacity, electrical resistivity, thermoelectric power, and Hall effect have been investigated on single-crystalline Ce2PdSi3. This compound is shown to order antiferromagnetically below Néel temperature (TN ) ∼ 3 K. The Sommerfeld coefficient far below TN is found to be about 110 mJ/K 2 mol Ce, which indicates the heavyfermion character of this compound. The transport and magnetic properties exhibit large anisotropy with an interplay between crystalline-electric-field (CEF) and Kondo effects. The sign of thermoelectric power is opposite for different directions at high temperatures and the ordinary Hall coefficient is anisotropic with opposite sign for different geometries, indicating the anisotropic Fermi surface. The CEF analysis from the temperature dependence of magnetic susceptibility suggests that the ground state is | ± 1 2 . The first and the second excited CEF doublet levels are found to be located at about 30 and 130 K, respectively. The Kondo temperature is estimated to be the same order as TN , indicating the presence of a delicate competition between the Kondo effect and magnetic order.

Crystal growth of the intermetallic compound Nd2PdSi3

“…This becomes already perceptible from the smooth appearance and the absence of ripples at the crystal surface [9]. At single crystalline R 2 TSi 3 specimen considerable anisotropy of the magnetic behavior, the giant negative magnetoresistance, and the magnetocaloric properties have been observed [3,4,8,[12][13][14].…”

“…First single crystals of this class of compounds, Gd 2 PdSi 3 [3] and Ce 2 PdSi 3 [4], were grown in 1999 by the tetra-arc Czochralski method. Simultaneously, floating zone (FZ) techniques with radio frequency inductive heating were successfully applied for compounds with Ce, Tb, Dy and Ho [5][6][7][8].…”

Electronic Structure and Nesting-Driven Enhancement of the RKKY Interaction at the Magnetic Ordering Propagation Vector inGd2PdSi3andTb2PdSi3Inosov1, Evtushinsky2, Koitzsch3 et al. 2009Phys. Rev. Lett.483230View full textAdd to dashboardCite

“…Comparison with neutron diffraction data from the same crystals shows perfect agreement of this vector with the propagation vector of the low-temperature in-plane magnetic order, thereby demonstrating the decisive role of the Fermi surface geometry in explaining the complex magnetically ordered ground state of ternary rare earth silicides. Ternary rare earth silicides with hexagonal crystal structure of the form R 2 PdSi 3 , where R is a rare earth atom, are known to exhibit complex magnetic behavior [1,2,3,4,5,6,7,8,9,10,11,12,13,14] Most of the R 2 PdSi 3 compounds order magnetically at low temperatures, somewhat below the Kondo minimum in the resistivity [2,3,4,5,6]. The exact type of such ordering strongly depends on the material and can be rather complicated [6,10].…”

“…The band bottom of both features lies at 0.5 eV below the Fermi level. From the experimentally measured band structure, we estimate the momentum-dependent RKKY coupling strength and demonstrate that it is peaked at the 1 2 ΓK wave vector. Comparison with neutron diffraction data from the same crystals shows perfect agreement of this vector with the propagation vector of the low-temperature in-plane magnetic order, thereby demonstrating the decisive role of the Fermi surface geometry in explaining the complex magnetically ordered ground state of ternary rare earth silicides.…”

“…Comparison with neutron diffraction data from the same crystals shows perfect agreement of this vector with the propagation vector of the low-temperature in-plane magnetic order, thereby demonstrating the decisive role of the Fermi surface geometry in explaining the complex magnetically ordered ground state of ternary rare earth silicides. Ternary rare earth silicides with hexagonal crystal structure of the form R 2 PdSi 3 , where R is a rare earth atom, are known to exhibit complex magnetic behavior [1,2,3,4,5,6,7,8,9,10,11,12,13,14] due to a delicate competition of the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction [15] and the Kondo effect, which are comparable in magnitude [1,2]. Such interplay determines many unusual magnetic, thermal, and transport properties, which stimulate unceasing interest to these materials during the last two decades: large negative magnetoresistance [3], quasi-lowdimensional magnetism and spin-glass-like behavior [7,8], highly anisotropic ac susceptibility [7], magnetocaloric effect [9], thermoelectric power [1], and Hall coefficient [1].…”