Cd doping effects in the heavy-fermion compoundsCe2MIn8(M=Rha

Abstract

Low-temperature magnetic properties of Cd-doped Ce 2 MIn 8 ͑M = Rh and Ir͒ single crystals are investigated. Experiments of temperature-dependent magnetic-susceptibility, heat-capacity, and electrical-resistivity measurements revealed that Cd doping enhances the antiferromagnetic ͑AFM͒ ordering temperature from T N = 2.8 K ͑x =0͒ to T N = 4.8 K ͑x = 0.21͒ for Ce 2 RhIn 8−x Cd x and induces long-range AFM ordering with T N = 3.8 K ͑x = 0.21͒ for Ce 2 IrIn 8−x Cd x . Additionally, x-ray and neutron magnetic scattering studies showed that Cd-doped samples present below T N a commensurate antiferromagnetic structure with a propagation vector ជ = ͑ 1 2 , 1 2 ,0͒. The resolved magnetic structures for both compounds indicate that the Cd doping tends to rotate the direction of the ordered magnetic moments toward the ab plane. This result suggests that the Cd doping affects the Ce 3+ ground-state single-ion anisotropy modifying the crystalline electrical field ͑CEF͒ parameters at the Ce 3+ site. Indications of CEF evolution induced by Cd doping were also found in the electrical-resistivity measurements. Comparisons between our results and the general effects of Cd doping on the related compounds CeMIn 5 ͑M = Co, Rh, and Ir͒ confirms the claims that the Cd doping induced electronic tuning is the main effect favoring AFM ordering in these compounds.

Physical properties and magnetic structure of the intermetallic CeCuBi2 compound

“…The magnetic coupling of the Ce atoms within the unit cell can be determined by comparing the experimental integrated intensity of several magnetic peaks with the calculated model (Eq. 1) [26][27][28].…”

Resonant and magnetic X-ray diffraction by polarized synchrotron radiation

“…This technique has been essential in a number of high-profile cases, as for example the orbital and charge ordering in transition metals [94][95][96][97][98][99][100][101], frustrated magnetism in low dimensional magnetic systems [102,103], multiferroics [104,105], heavy fermion antiferromagnets [106,107], picnide superconductors [108][109][110], magnetic thin films and multilayers [111,112].…”

Spin rotation induced by applied pressure in the Cd-doped Ce2RhIn8 intermetallic compound

“…For Ce MIn 5 (m = 1, n = 1) it was found that Cd suppresses the superconductivity for M = Co and Ir while it tends to favor AFM ordering for M = Rh [8,9]. For Ce 2 MIn 8 (m = 2, n = 1: Ce 218) Cd doping increases the T N for M = Rh and induces a long range magnetically ordered phase for M = Ir [10]. All these previous results suggested that Cd is acting as an electronic tuning agent that induces a decrease of the local density of states at the Ce 3+ site which tends to reduce the Kondo effect and favor AFM ordering [11,12].…”