Ferromagnetism emerged from non-ferromagnetic atomic crystals.

The recently emerged ferromagnetic two-dimensional (2D) materials provide unique platforms for compact spintronic devices down to the atomic-thin regime; however, the prospect is hindered by the limited number  of ferromagnetic 2D materials discovered with limited choices of magnetic properties. If 2D antiferromagnetism could be converted to 2D ferromagnetism, the range of 2D magnets and their potential applications would be significantly broadened. Here, we discovered emergent ferromagnetism by interfacing non-magnetic WS2 layers with the antiferromagnetic FePS3. The WS2 exhibits an order of magnitude enhanced Zeeman effect with a saturated interfacial exchange field ~38 Tesla. Given the pristine FePS3 is an intralayer antiferromagnet, the prominent interfacial exchange field suggests the formation of ferromagnetic FePS3 at interface. Furthermore, the enhanced Zeeman effect in WS2 is found to exhibit a strong WS2-thickness dependence, highlighting the layer-tailorable interfacial exchange coupling in WS2-FePS3 heterostructures, which is potentially attributed to the thickness-dependent interfacial hybridization.

Light-Induced Paramagnetism in Colloidal Ag+-Doped CdSe Nanoplatelets.

We describe a study of the magneto-optical properties of Ag+-doped CdSe colloidal nanoplatelets (NPLs) that were grown using a novel doping technique. In this work, we used magnetic circularly polarized luminescence and magnetic circular dichroism spectroscopy to study light-induced magnetism for the first time in 2D solution-processed structures doped with nominally nonmagnetic Ag+ impurities. The excitonic circular polarization (PX) and the exciton Zeeman splitting (ΔEZ) were recorded as a function of the magnetic field (B) and temperature (T). Both ΔEZ and PX have a Brillouin-function-like dependence on B and T, verifying the presence of paramagnetism in Ag+-doped CdSe NPLs. The observed light-induced magnetism is attributed to the transformation of nonmagnetic Ag+ ions into Ag2+, which have a nonzero magnetic moment. This work points to the possibility of incorporating these nanoplatelets into spintronic devices, in which light can be used to control the spin injection.

High-Fidelity Transfer of Chemical Vapor Deposition Grown 2D Transition Metal Dichalcogenides via Substrate Decoupling and Polymer/Small Molecule Composite.

Current polymeric transfer methods of 2D materials often bring about the presence of wrinkles, cracks, and polymer residue, limiting the quality of the transferred materials and performance of devices. Herein, we report a transfer approach combining pretreatment by liquid nitrogen and lithium ion intercalation with polymer composite of small molecules and polystyrene to achieve high-fidelity transfer of 2D transition metal dichalcogenides (TMDs) grown by chemical vapor deposition. In this method, the as-grown samples were pretreated by liquid nitrogen and lithium ion intercalation to weaken the bonding between the TMD and the substrate. A polymer composite incorporating small molecules, namely camphor or naphthalene, was used to increase the dissolution of the polymer film. These two processes work synergistically to enable nearly 100% transfer of monolayer TMDs virtually free of wrinkles, cracks, or organic residue with retained optical properties. Our technique can be generalized for the efficient and high quality transfer of other 2D materials.

Educational level and age as contributing factors to road traffic accidents.

OBJECTIVE: This research analyzes data on road traffic accidents (RTA) in Fars province, whose roads are among the highly dangerous ones in Iran. It investigates educational level and age involved in RTA in order to discover patterns that can prevent or decrease accidents. METHODS: This research made use of data visualization techniques to find hidden patterns. The data included mortality rate related to RTA in Fars province and were obtained from Fars Forensic Medicine Registry covering a period of 1 year from March 21, 2010 to March 21, 2011. All data were analyzed using SPSS 11.5. The results were reported as descriptive indices such as frequency (percentage). The Chi-square test was applied to the data concerning educational level and age. P value less than 0.05 was considered significant. RESULTS: In the mentioned period, 1 831 people were killed, out of whom un/lowly educated people (69.6%) accounted for the highest mortality rate. The significant relationship between educational level and mortality rate was found (X2 equal to 275.98, P less than 0.0001).Also three was a significant association between age and mortality rate (X2 equal to 371.20, P less than 0.0001). Young people (age between 20 and 29 years) contribute to higher RTA mortality rate compared with other age groups. CONCLUSION: The educational level and age are significantly correlated to mortality rate. The youth and un/lowly educated people suffer more fatal RTA.