Magnetization and magnetocrystalline anisotropy of R2Fe17 intermetallics under pressure

Abstract

The measurements of magnetization and magnetic anisotropy of R2Fe17 (R=Y, Er, Ho, and Gd) single crystals were performed under hydrostatic pressure up to 1 GPa, in temperature range 5–300 K and at magnetic fields up to 5 T, using the SQUID magnetometer with a miniature pressure CuBe cell. A pronounced decrease of spontaneous magnetization M of the R2Fe17 intermetallics has been observed under pressure. The values of dM/dp vary in an interval from −0.32μB/f.u. per kbar (Y2Fe17) up to −0.1μB/f.u. per kbar (Ho2Fe17). The R elements in the R2Fe17 intermetallics have a strong influence on the d(ln mFe)/dp values at 5 K. A remarkable decrease of the anisotropy constant with pressure, d ln K1/dp=−1.7×10−2 kbar−1 at 5 K, was observed on the Y2Fe17 compound. In the Gd2Fe17 compound, |K1(T)| increases with increasing pressure below 150 K and decreases with increasing pressure above this temperature value. The critical field HC(T) of the FOMP in the Er2Fe17 compound exhibits a similar behavior, it increases under pressure at temperatures below 60 K and decreases at higher temperatures.