High Field Magnetization of RMn₂

Abstract

The high field magnetization of RMn₂, where R stands for a rare-earth element, has been measured at 4.2 K by using pulsed magnetic fields up to about 300 kOe. The magnetizations of YMn₂, PrMn₂, NdMn₂ and SmMn₂ increase almost linearly with increasing magnetic field. The magnetization curves of GdMn₂, TbMn₂, DyMn₂, HoMn₂ and BrMn₂ show a trend of saturation at high fields. The saturation magnetic moments per formula unit were estimated as 6.2 μ_B, 9.5 μ_B, 10.0 μ_B, 10.3 μ_B, 10.1 μ_B and 8.9 μ_B for GdMn₂, TbMn₂, DyMn₂, HoMn₂(C15), HoMn₂(C14) and ErMn₂, respectively. These values are in agreement with the R³⁺ moments except for GdMn₂. The analysis on GdMn₂ excludes particularly a simple ferrimagnetic coupling between Gd and Mn moments.