相关论文: Magnetic oxide semiconductors
A close link between the charge transfer electronic structures and polarity dependent high-TC ferromagnetism of TM2+:ZnO DMSs (TM2+ = 3d ions) is demonstrated. Trends in ferromagnetism across the 3d series of TM2+:ZnO DMSs predicted from…
Realistic oxide materials are often semiconductors, in particular at elevated temperatures, and their surfaces contain undercoordiated atoms at structural defects such as steps and corners. Using hybrid density-functional theory and ab…
We provide an overview of progress on the exchange biasing of a ferromagnetic semiconductor (Ga1-xMnxAs) by proximity to an antiferromagnetic oxide layer (MnO). We present a detailed characterization study of the antiferromagnetic layer…
A (II,Mn)VI diluted magnetic semiconductor quantum dot with an integer number of electrons controlled with a gate voltage is considered. We show that a single conduction band electron is able to induce a spontaneous collective magnetization…
Recent progress in understanding and controlling spintronic properties of (Ga,Mn)As and related compounds is contrasted to diverging experimental and theoretical results concerning the origin of high temperature ferromagnetism discovered in…
Structural and magnetic properties have been studied for polycrystalline Zn_{1-x}TM_xO, where TM (transition metal ions) = Mn, Fe, and Co. No bulk ferromagnetism was observed for single-phase materials, contrary to the existing theories.…
So far, magneto-ionics, understood as voltage-driven ion transport in magnetic materials, has largely relied on controlled migration of oxygen ion/vacancy and, to a lesser extent, lithium and hydrogen. Here, we demonstrate efficient,…
Since 2000, the intensive effort in materials research to develop a diluted magnetic semiconductor exhibiting high-temperature (HT) ferromagnetism above room temperature was not successful. Here, the possible first bulk diluted…
We have investigated the room temperature ferromagnetic order that develops in Al-substituted magnesium oxide, Mg(Al)O, nanoparticles with Al fractions of up to 5 at.%. All samples, including undoped MgO nanoparticles, exhibit room…
We present a theoretical survey of ferromagnetic transition temperatures in cubic (III,Mn)V semiconductors based on a model with $S=5/2$ local moments exchange-coupled to itinerant holes in the host semiconductor valence band. Starting from…
Ferromagnetic semiconductors promise the extension of metal-based spintronics into a material system that combines widely tunable electronic, optical, and magnetic properties. Here, we take steps towards realizing that promise by achieving…
The electronic structure and magnetic exchange interactions in pure and V-doped Fe16N2 are studied within the framework of density functional theory. The Curie temperatures were obtained with both mean field approximation (MFA) as well as…
The correlation between magnetic properties and microscopic structural aspects in the diluted magnetic semiconductor Ge$_{1-x}$Mn$_{x}$Te is investigated by x-ray diffraction and magnetization as a function of the Mn concentration $x$. The…
We report a surfactant assisted synthesis of Mn doped ZnO polycrystalline samples showing robust room temperature ferromagnetism as characterized by X-ray diffraction analysis, Transmission Electron Microscopy, Electron Paramagnetic…
A density functional theory of ferromagnetism in heterostructures of compound semiconductors doped with magnetic impurities is presented. The variable functions in the density functional theory are the charge and spin densities of the…
During the past years there has been renewed interest in the wide-bandgap II-VI semiconductor ZnO, triggered by promising prospects for spintronic applications. First, ferromagnetism was predicted for dilute magnetic doping. In…
Electric control of magnetism is a vision which drives intense research on magnetic semiconductors and multiferroics. Recently, also ultrathin metallic films were reported to show magnetoelectric effects at room temperature. Here we…
After more than a decade of intensive research in the field of diluted magnetic semiconductors (DMS), the nature and origin of ferromagnetism, especially in III-V compounds is still controversial. Many questions and open issues are under…
The magnetic and transport behaviors of cerium substituted iron oxy-arsenide superconductor with x = 0.1 to 0.4 fluoride (F) doping have been investigated in this report. Temperature dependent susceptibility and resistivity measurements…
The possibility that the apparent room temperature ferromagnetism, often measured in Co-doped ZnO, is due to uncompensated spins at the surface of wurtzite CoO nanoclusters is investigated by means of a combination of density functional…