Evolution of the Magnetic Properties in the Antiferromagnet Ce2RhIn8 Simultaneously Doped with Cd and Ir

Published

November 20, 2020

Author(s)

D. S. Christovam, G. S. Freitas, M. M. Piva, J. C. Souza, M. O. Malcolms, O. L. Canton, Juscelino Leao, William D. Ratcliff, Jeffrey W. Lynn, C. Adriano, P. G. Pagliuso

Abstract

We report the evolution of the magnetic properties of Ce₂Rh_1−xIr_xIn_8−yCd_y single crystals. In particular, for Ce₂Rh_0.5Ir_0.5In₈ (T_N = 2.0 K) and Ce₂Rh_0.5Ir_0.5In_7.79Cd_0.21 (T_N = 4.2 K), we have solved the magnetic structure of these compounds using single crystal neutron magnetic diffraction experiments. Taking the magnetic structure of Ce₂RhIn₈ heavy fermion antiferromagnet as a reference, we have identified no changes in the q = (1/2, 1/2, 0) magnetic wave vector, however the direction of the ordered Ce³⁺ moments rotates toward the ab-plane, under the influence of both dopants. By constraining the analysis of the crystalline electric field (CEF) with the experimental ordered moment's direction and high-temperature magnetic susceptibility data, we have used a mean field model with tetragonal CEF and exchange interactions to gain insight into the CEF scheme and anisotropy of the CEF ground state wave function when Cd and Ir are introduced into Ce₂RhIn₈. Consistent with previous work, we find that Cd-doping in Ce₂RhIn₈ tends to rotate the magnetic moment toward the ab-plane and lower the energy of the CEF excited states levels. Interestingly, the presence of Ir also rotates the magnetic moment towards the ab-plane although its connection to the CEF overall splitting evolution for the y = 0 samples may be not straightforward. These findings may shed light on the origin of the disordered spin-glass phase in the Ir-rich side of the phase diagram and also indicates that the Ce₂MIn₈ compounds may not follow exactly the same Rh-Ir CEF effects trend established for the CeMIn₅ compounds.

Citation

Physical Review B

Volume

102

Issue

19

Pub Type

Journals

Keywords

Magnetic Structures, Magnetic phase transitions, single crystals, susceptibility, crystal field effects.

Citation

Christovam, D. , Freitas, G. , Piva, M. , Souza, J. , Malcolms, M. , Canton, O. , Leao, J. , Ratcliff, W. , Lynn, J. , Adriano, C. and Pagliuso, P. (2020), Evolution of the Magnetic Properties in the Antiferromagnet Ce₂RhIn₈ Simultaneously Doped with Cd and Ir, Physical Review B (Accessed December 21, 2024)