CoO/Al-doped ZnO (AZO) multilayers exhibit ferromagnetism up to ~300 K. The magnetic behavior oscillates with odd vs even number of Co layers in the insulating antiferromagnetic CoO and (separately) with the thickness of the AZO layers and vanishes if AZO is replaced by intrinsic ZnO. Magnetization is due to uncompensated (111) ferromagnetic planes of insulating CoO for odd numbers of atomic planes per layer that are coupled together via RKKY exchange mediated by electron carriers in the nonmagnetic AZO layers. The period of the oscillation with AZO thickness qualitatively matches the Fermi wave vector calculated from the carrier concentration measured by ordinary Hall effect. Magnetic polarization of the AZO carriers is confirmed via an anomalous Hall effect that is proportional to the magnetization.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1103/PhysRevLett.110.087206 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Preparation and Characterization of the MMT@FeO@Ag Nanocomposite for Catalytic Degradation of Methyl Yellow: Reaction Parameters and Mechanism Based on the Artificial Neuron Network.
ACS Omega
January 2025
Department of Chemistry, Selcuk University, Konya 42130, Turkey.
The montmorillonite@iron oxide@silver (MMT@FeO@Ag) nanocomposite, which is recyclable and exhibits high catalytic activity, was evaluated for the degradation of methyl yellow (MY), a carcinogenic azo dye. For this purpose, MMT@FeO was first synthesized via the coprecipitation method and then Ag was doped to MMT@FeO via the chemical reduction method. MMT, MMT@FeO, and MMT@FeO@Ag were characterized by various techniques including scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, vibrating sample magnetometer, and thermal gravimetric analysis.
View Article and Find Full Text PDFInvestigating the link between a layer thickness and surface relief depth in an azo poly(ether imide).
Sci Rep
January 2025
Faculty of Physics, Warsaw University of Technology, 75 Koszykowa Str., 00-662, Warszawa, Poland.
Surface relief grating formation in photo-responsive azo polymers under irradiation is a long-ago-found phenomenon, but all the factors governing its efficiency are still not fully recognized. Here, we report on the enormous impact of the polymer thickness on the possibility of fabrication of extremely high-amplitude surface deformations. We performed prolonged holographic recordings on the layers of the same azobenzene poly(ether imide), which had substantially different optical transmittances at the recording wavelength and revealed that the depths of the inscribed relief structures increased with the polymer thickness from a nondetectable value up to almost 2 µm, unaffected by the presence of a polymer-glass substrate interface in either sample.
View Article and Find Full Text PDFInvestigation of the Relationship Between Brown HT Dye Exposure and Mammary Tumor Development in Female Rats: An Assessment of the Potential Risk of Breast Cancer.
Cureus
November 2024
Department of Applied Nutrition and Food Technology, Islamic University, Kushtia, BGD.
Article Synopsis
- * Female Long-Evans rats were divided into groups to assess the effects of E155 on tumor development, with some receiving the dye in various doses over 40 weeks compared to control groups.
- * Results showed that higher E155 doses led to significant weight loss, renal impairment, liver dysfunction, and an increased incidence of mammary tumors, suggesting that prolonged exposure could heighten breast cancer risk.
Exploring the impact of washing media on the adsorption properties of Mg-Al Layered Double Hydroxide Nanoparticles.
Chemosphere
December 2024
MAPS (Materials' Process - Structure correlations) Laboratory, Metallurgical and Materials Engineering, Indian Institute of Technology Patna, Bihta, Bihar, 801106, India. Electronic address:
Environmental remediation has emerged as a critical concern, with dye removal via adsorption being a particularly effective approach. This study demonstrates that appropriately synthesized Mg-Al-Layered Double Hydroxides (LDHs) exhibit exceptional adsorption capacities for anionic dyes. We investigate the impact of different washing media on the material's morphology, surface area, and adsorption capabilities.
View Article and Find Full Text PDFVertical Electric-Field-Induced Switching from Strong to Asymmetric Strong-Weak Confinement in GaAs Cone-Shell Quantum Dots Using Transparent Al-Doped ZnO Gates.
Nanomaterials (Basel)
October 2024
Center for Hybrid Nanostructures (CHyN), University of Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany.
Article Synopsis
- The research evaluates Al-doped ZnO (AZO) as a transparent gate material, finding it enhances quantum dot emission intensity over traditional Ti gates, while also noting issues with charge artifacts at higher gate voltages.
- It also explores switching behaviors in GaAs cone-shell quantum dots (CSQDs) under vertical electric fields, observing localized charge carrier densities and minimal interference from interface charges at low voltages.
- The findings reveal a new asymmetric strong-weak confinement in quantum dots, where the hole transitions from strong to weak confinement while the electron remains strongly confined, supporting theoretical predictions regarding hole probability densities.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!