Ultrathin Nanocrystalline Magnetic Wires

Abstract

Abstract:The magnetic characteristics of FINEMET type glass-coated nanowires and submicron wires are investigated by taking into account the structural evolution induced by specific annealing all the way from a fully amorphous state to a nanocrystalline structure. The differences between the magnetic properties of these ultrathin wires and those of the thicker glass-coated microwires and "conventional" wires with similar structures have been emphasized and explained phenomenologically. The domain wall propagation in these novel nanowires and submicron wires, featuring a combination between an amorphous and a crystalline structure, has also been studied, given the recent interest in the preparation and investigation of new materials suitable for the development of domain wall logic applications.

Stress-Induced Magnetic Anisotropy Enabling Engineering of Magnetic Softness and GMI Effect of Amorphous Microwires

“…Magnetic wires exhibit versatile physical properties such as the Giant Magnetoimpedance (GMI) effect [1][2][3] and fast propagation of a single domain wall (DW) [4,5]. Although these properties are not solely restricted to amorphous magnetic wires [3,6], the former family presents several advantages, like better mechanical properties [7,8] as well as a fast and inexpensive preparation method involving rapid solidification from the melt [9][10][11]. Consequently, the highest GMI effect and the fastest DW propagation were reported in either Co-rich or Fe-rich amorphous microwires, respectively [4, 5,[12][13][14].…”

“…Consequently, metamaterials incorporating arrays of magnetic wires in fiber-reinforced polymer composites are potentially suitable for engineering of electromagnetic functionalities and stress/temperature monitoring.Industrial applications based on the GMI effect demand a size reduction of the magnetic element [16,17]. Therefore, the development of thin wires exhibiting GMI effect has become a topic of intensive research [4,5,[11][12][13][14][15]. Among different preparation techniques of magnetic wires, the so-called Taylor-Ulitovsky method allows for the thinnest wires' fabrication and reduced dimensions [11][12][13][14][15][16][31][32][33].…”

“…Therefore, the development of thin wires exhibiting GMI effect has become a topic of intensive research [4,5,[11][12][13][14][15]. Among different preparation techniques of magnetic wires, the so-called Taylor-Ulitovsky method allows for the thinnest wires' fabrication and reduced dimensions [11][12][13][14][15][16][31][32][33]. In order to observe the GMI effect in thin wires, the skin depth should be lower than the radius of the wire.…”

“…As such, a decrease in diameter should be associated with an increase in the frequency range for observation of the GMI effect [34,35]. Besides these technical features, the overall cost should be also considered for applications (e.g., smart composites with wire inclusions) where substantial amounts of wires are required.Excellent soft magnetic properties with enhanced GMI effects are usually reported for as-prepared Co-rich [11][12][13][14][15] and nanocrystalline Fe-rich magnetic microwires [36,37]. The latter are often accompanied with an inherent brittleness of samples over the course of the nanocrystallization process, and therefore alternative stress-annealing approaches have been proposed, to enhance the GMI effect retaining the amorphous structure [38,39].…”

Engineering of Magnetic Properties of Magnetic Microwires

“…• thinnest metallic nucleus diameter among the magnetic wires prepared using casting methods families [27,28];…”