Nanoscale-driven single-domain structure in nickel substituted superparamagnetic cobalt ferrites

Abstract

In this letter, we reported nickel substituted cobalt nano-ferrites of ∼ 5 nm particle size synthesized with forced hydrolysis methods. The magnitude of the anisotropy constant decreases from 6.06 × 105 to 2.45 × 104 erg/cm3 due to the 𝑁 𝑖2+ doping. Whereas the gradual increment of 𝑁 𝑖2+ ions decreases the blocking temperature from ∼182 k to ∼52 K. The single-domain superparamagnetic behaviour observed here above the blocking temperature. This behaviour could help the material be a promising candidate in quantum technologies as a bit for storage devices.