Tuneable magnetic phase transitions in layered CeMn2Ge2-xSix compounds

Authors

M F. Md Din, University of WollongongFollow
Jianli Wang, University of WollongongFollow
Zhenxiang Cheng, University of WollongongFollow
S X. Dou, University of WollongongFollow
Shane J. Kennedy, ANSTO, Bragg Institute, AnstoFollow
Maxim Avdeev, ANSTO
Stewart J. Campbell, University of New South WalesFollow

RIS ID

101695

Publication Details

Md Din, M. F., Wang, J. L., Cheng, Z. X., Dou, S. X., Kennedy, S. J., Avdeev, M. & Campbell, S. J. (2015). Tuneable magnetic phase transitions in layered CeMn₂Ge_2-xSi_x compounds. Scientific Reports, 5 11288-1-11288-15.

Abstract

The structural and magnetic properties of seven CeMn₂Ge_2-xSi_x compounds with x = 0.0-2.0 have been investigated in detail. Substitution of Ge with Si leads to a monotonic decrease of both a and c along with concomitant contraction of the unit cell volume and significant modifications of the magnetic states - a crossover from ferromagnetism at room temperature for Ge-rich compounds to antiferromagnetism for Si-rich compounds. The magnetic phase diagram has been constructed over the full range of CeMn₂Ge_2-xSi_x compositions and co-existence of ferromagnetism and antiferromagnetism has been observed in CeMn₂Ge_1.2Si_0.8, CeMn₂Ge_1.0Si_1.0 and CeMn₂Ge_0.8Si_1.2 with novel insight provided by high resolution neutron and X-ray synchrotron radiation studies. CeMn₂Ge_2-xSi_x compounds (x = 0, 0.4 and 0.8) exhibit moderate isothermal magnetic entropy accompanied with a second-order phase transition around room temperature. Analysis of critical behaviour in the vicinity of T_C^inter for CeMn₂Ge₂ compound indicates behaviour consistent with three-dimensional Heisenberg model predictions.

Grant Number

ARC/DP0879070, ARC/DP110102386, ARC/DP120100095

Additional Grant Number

http://purl.org/au-research/grants/ARC/DP0879070

http://purl.org/au-research/grants/ARC/DP110102386

http://purl.org/au-research/grants/ARC/DP120100095