Pressure-induced new spin-states in Ni-25at%Mn mechanical alloy under high pressure

[摘要] AC-susceptibility measurements in mechanically alloyed Ni-25at%Mn were made under high hydrostatic pressures up to 7.5 GPa by using a cubic anvil press in the low-temperature range from 4.2 K to 300 K. At ambient pressure a reentrant spin glass (RSG) state was observed below 58 K, followed by a ferromagnetic (FM) state with the Curie temperature (TC ) at 120 K. Tc decreased with increasing pressure up to 4.3 GPa, while the transition temperature from RSG to FM increased to merge with Tc at 70 K, and then, with further increasing pressure the FM state disappeared, and a spin glass (SG) state appeared. The local moments of this high-pressure SG phase decreased with pressure. The results were compared with a bulk alloy made by the conventional method of melting. In the bulk alloy, a new high-pressure magnetic phase appeared having almost pressure-independent local magnetic moments.

[发布机构] Advanced Materials Developing Center, Research Laboratories, JFE Mineral Co. Ltd, 1 Niihamacho, Chiba; 260-0826, Japan^1;Institute of Physics, Cracow University of Technology, Cracow, Poland^2;Okayama University of Science, 1-1 Ridaicho, Kitaku, Okayama; 700-0005, Japan^3

[效力级别] 材料科学

[关键词] Ac-susceptibility measurements;Ambient pressures;Conventional methods;High hydrostatic pressure;Local magnetic moments;Low temperatures;Mechanically alloyed;Reentrant spin glass