On the origin of the giant isotopic effect of hydrogen on the magnetic properties of YFe2A4.2 (A5H, D): A high pressure study

Olivier Isnard (1) , Valérie Paul-Boncour (2) , Zdenek Arnold (3)

1 NEEL - MRS - Matériaux, Rayonnements, Structure
2 ICMPE - Institut de Chimie et des Matériaux Paris-Est
3 Institute of Physics [Prague]

In order to identify the origin of the giant isotope effect observed on the magnetic properties of YFe2A4.2 compounds (A¼H, D) and probe the role of the cell volume difference, we have compared the effect of hydrostatic pressure up to 1.0 GPa on the ferro-antiferromagnetic transition temperatures TF-AF and spontaneous magnetization of YFe2D4.2 and YFe2H4.2. Using compressibility value of 0.013 GPa 1 and the remarkably different negative pressure slopes of TF-AF, the existence of critical volume where the ferromagnetism is suppressed at 0K, VC¼501.760.3 ˚A3, was demonstrated. This consequently established the crucial role of volume on the huge isotope effect observed on the magnetic properties.

Mots clés: hydride; Fe magnetism; laves phase

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Olivier Isnard, Valérie Paul-Boncour, Zdenek Arnold. On the origin of the giant isotopic effect of hydrogen on the magnetic properties of YFe2A4.2 (A5H, D): A high pressure study. Applied Physics Letters, 2013, 102, pp.122408. ⟨10.1063/1.4798260⟩. ⟨hal-00955355⟩