Influence of Electron Doping on Magnetic Order in CeRu2Al10

The effect of electron doping by the substitution of Rh for Ru on unconventional magnetic order in CeRu2Al10 was investigated via neutron powder diffraction. In Ce(Ru1-xRhx)2Al10 with x = 0.05, 0.12, and 0.2, reorientation of the ordered moment from the c- to the a-axis takes place in all samples, while the ordering vector q=(0 1 0) remains unchanged within this concentration range. The moment reorientation is accompanied by an enhancement in its size by a factor of ~2.4, from μ=0.43 μB at x=0 to μ =1.06, 1.04, and 1.02 μB for x=0.05, 0.12 and 0.2, respectively. The continuous decrease in N´eel temperature T0(TN), despite an abrupt increase in μ , underlines the strong anisotropy in the exchange interaction in CeRu2Al10, and the fact that this anisotropy is easily suppressed by electron doping.