Nano-Structured Dilute Magnetic Semiconductors for Efficient Spintronics at Room Temperature

Abstract

In recent years, many efforts have been made to develop advanced metal oxide semiconductor nanomaterials with exotic magnetic properties for modern applications w.r.t traditional analogues. Dilute magnetic semiconductor oxides (DMSOs) are promising candidates for superior control over the charge and spin degrees of freedom. DMSOs are transparent, wide band gap materials with induced ferromagnetism in doping, with a minor percentage of magnetic 3d cation to create a long-range antiferromagnetic order. Although significant efforts have been carried out to achieve DMSO with ferromagnetic properties above room temperature, it is a great challenge that still exists. However, TiO2, SnO2, ZnO and In2O3 with wide band gaps of 3.2, 3.6, 3.2 and 2.92 eV, respectively, can host a broad range of dopants to generate various compositions. Interestingly, a reduction in the size of these binary oxides can induce ferromagnetism, even at room temperature, due to the grain boundary, presence of defects and oxygen vacancies. The present review provides a panorama of the structural analysis and magnetic properties of DMSOs based on binary metal oxides nanomaterials with various ferromagnetic or paramagnetic dopants, e.g., Co, V, Fe and Ni, which exhibit enhanced ferromagnetic behaviors at room temperature.

Microwave Synthesis of Hematene and Other Two-Dimensional Oxides

“…Metal oxides are interesting inorganic compounds that have variable oxidation states that are dependent on the metal’s valency. Even a metal oxide with a particular oxidation state can exist in various crystallographic phases. − Variety of applications of metal oxides have already been explored in nanomaterials systems (nanoparticles, nanowires, and thin films) such as dielectric barriers in field-effect transistors; in magnetic tunnel junctions; in dilute magnetic semiconductors; in energy harvesting; in light-emitting diodes, photosensing, humidity sensing, and molecular sensing; and in energy generation and storage; as well as in visible or UV catalysis, depending on its band gaps. − Moreover, low loss dielectrics are good for microwave communication applications. In industrial machine components and in miniaturized devices, metal oxide can be used as an antioxidation and anticorrosion coating. − With the ever-changing technological needs of miniaturized devices and sensors, the need for exploring two-dimensional phases of metal oxides (2DMOs) is timely and urgent.…”

Electrical Transport and Magnetic Properties of Metal/Metal Oxide/Metal Junctions Based on Anodized Metal Oxides

“…For example, growing attention is observed for magnetic semiconductors, i.e. diluted semiconductors like doped titanium oxides [3,4] and not-diluted semiconductors like hematite [5], also the magnetic half-metals, such as magnetite, experience large interest [6]. For instance, the junctions composed of the titanium-and iron-based metal oxides being the main purpose of this study are widely considered for electronics and spintronics [7,8].…”

Ortho-atomic projector assisted DFT+U study of room temperature Ferro- and antiferromagnetic Mn-doped TiO2 diluted magnetic semiconductor

“…Introducing magnetic impurities into such semiconducting oxides has generated a lot of interest in recent years as a result of its uncommon ability to mix existing semiconducting behavior with substantial magnetism [5,15] and is referred to as dilute magnetic oxide semiconductors (DMOS). TiO 2 is a notable and commonly utilized semiconductor with rutile and anatase structures and a large bandgap that is well altered through doping, for versatile optical, electronic, and magnetic properties [16].…”