Pressure induced non-collinear magnetic structures in Fe-rich intermetallics

The results of a complementary study of magnetic properties, magnetovolume effects and neutron diffraction studies under pressure in R₂Fe₁₇ compounds with non-magnetic R (R - Y, Ce, Lu) are presented. The collinear ferromagnetic phase existing at low temperature in all three compounds is suppressed at high pressures. The critical pressure P _C depends on the compound studied (P _C ≅ 2.5 kbar for Ce₂Fe₁₇, P _C ≅ 3.5 kbar for Lu₂Fe₁₇, P _C ≅ 12 kbar for Y₂Fe₁₇). Incommensurate non-collinear magnetic structures that replace the ferromagnetic ones under high pressures have similar features - magnetic moments in each layer of atoms (perpendicular to z-axis) are parallel each other, their direction helically changes from layer to layer. A generalised phase diagram of the studied R₂Fe₁₇ compounds was determined with use of the recent compressibility data.

Keywords:

• Intermetallic Compounds
• R2fe17
• Pressure Effect
• Magnetic Structure