Nashaat Ahmed M, Kassem Mohamed A, Abu El-Fadl Abdulaziz, Nakamura Hiroyuki
Department of Physics, Faculty of Science, Assiut University, 71516 Assiut, Egypt.
Lab. of Smart Materials for Energy Futures, Faculty of Science, Assiut University, Assiut 71516, Egypt.
Nanotechnology. 2024 Feb 19;35(19). doi: 10.1088/1361-6528/ad2453.
NiCrOnanoparticles with average particle size ∼15 nm, a single-domain size maintains the bulk canted antiferromagnetic ground state, were synthesized by a microwave combustion method. The magnetic behavior was carefully investigated by static and dynamic magnetic susceptibility measurements. In addition to a spin-glass-like behavior below paramagnetic-ferrimagnetic transition at, the NiCrOnanoparticles demonstrate a low-temperature cluster spin glass transition below the spin canting transition, which manifests itself as a magnetic anomaly peak around ∼12 K (at 100 Oe) in the zero-field cooled magnetization with a relatively stronger field dependence in a 'de Almeida-Thouless' line for spin glasses. The AC susceptibility analyses in different approaches demonstrate a larger relative peak temperature variation per frequency decade and a longer characteristic relaxation time in the order of 0.04 and 10s, against 0.01 and 10s for the high-temperature blocking, indicating the slow spin dynamics for the low-temperature cluster glassy phase. A field-temperature magnetic phase diagram is proposed for the single-domain NiCrOnanoparticles.
