Publications by authors named "Z Barkay"
The Smith-Purcell effect allows for coherent free-electron-driven compact light sources over the entire electromagnetic spectrum. Intriguing interaction regimes, with prospects for quantum optical applications, are expected when the driving free electron enters the sub-keV range, though this has until now remained an experimental challenge. Here, we demonstrate the Smith-Purcell light emission from UV to visible using engineerable, fabricated gratings with periodicities as low as 19 nm and with electron energies as low as 300 eV.
View Article and Find Full Text PDFSequential Solidification of Metal Powder by a Scanning Microwave Applicator.
Materials (Basel)
January 2023
Article Synopsis
- The study explores the use of localized microwave heating (LMH) in a continuous process for solidifying metal powder, comparing it to traditional laser-based additive manufacturing techniques.
- Researchers implemented LMH in a lateral scanning method, successfully solidifying bronze powder at a rate of ~1 mm/s, creating solid bars with rough surfaces.
- The resulting products showed similar hardness and density properties to those made with laser methods, and the research assesses both the potential advantages and limitations of this LMH approach in metal manufacturing.
Article Synopsis
- This paper examines the elastic properties of Ti6Al4V alloy in four manufacturing conditions, revealing differences in Young's modulus, shear modulus, and Poisson's ratio.
- A specially designed sample was used to measure sound wave velocities, helping to derive elastic constant tensors and 3D Young's modulus maps, while EBSD and μCT techniques analyzed grain structures and defects.
- Findings indicate that AM materials are less anisotropic than hot rolled alloys; the study emphasizes the importance of manufacturing methods and orientations in material properties for better mechanical design and quality control.
Article Synopsis
- Recent advancements in soft electronics and applications like soft robotics and health monitoring emphasize the need for materials that maintain softness while offering electrical conductivity.
- Traditional conductive fillers compromise the mechanical properties (like softness and elasticity) of rubbers.
- This research presents a composite of vinyl methyl silicone rubber and multi-walled carbon nanotubes (MWCNTs), highlighting its conductive capabilities (comparable to carbon black-based options) with minimal hardness and excellent elastic recovery, along with self-sensing properties.
Article Synopsis
- Surveys in Eilat's upper mesophotic coral ecosystem revealed that colonies of the Sinularia octocoral create unique columnar structures known as spiculites, marking a new finding in coral reef studies.
- The research focused on understanding the spatial distribution, microstructure, and elemental makeup of these spiculites, confirming they are produced exclusively by the species S. vrijmoethi.
- Advanced analysis techniques showed that the spiculites consist of both magnesium-calcite sclerites and crystallites, suggesting the living coral may gain benefits from improved water flow due to these protruding structures.