Anisotropy distribution in rapidly quenched amorphous glass-coated nanowires

A new class of rapidly quenched composite nanomaterials, the amorphous glass-coated nanowires, has been recently developed [1]. They consist of a metallic nucleus enclosed in a glass coating. It has been shown that nanowires with large magnetostriction (λ >> 0), such as Fe-based ones, and those with vanishing magnetostriction (λ ≈ 0), e.g. Co-based ones with a small amount of Fe, exhibit rectangular hysteresis loops due to a single-step magnetization reversal which occurs when the axially applied magnetic field is larger than the switching field, process known as magnetic bistability. In contrast, rapidly quenched amorphous glass-coated microwires with similar compositions exhibit radically different magnetic behavior: magnetostrictive ones are magnetically bistable, whilst zero-magnetostrictive samples present an anhysteretic behavior [2]. Hence, a systematic analysis is required to clarify the observed behavior of amorphous nanowires with different magnetostriction constants.