Nov_Dec_AMP_Digital

1 0 A D V A N C E D M A T E R I A L S & P R O C E S S E S | N O V E M B E R / D E C E M B E R 2 0 2 0 A typical SQUID consists of a superconducting ring interrupted at two points by an extremely thin film with normal conducting or insulating properties. Researchers have recently begun using nanomaterials such as nanotubes, nanowires, or graphene to fashion the weak links connecting the two superconductors. The tiny device for measuring magnetic fields is only around 10 nano- meters high. The instrument can trigger supercurrents that flow in minuscule spaces. Moreover, its sensitivity can be adjusted by changing the distance between the graphene layers. With the help of electrical fields, the research- ers are also able to increase the signal strength, further enhancing the mea- surement accuracy. In the future, SQUIDs could also be used as low-noise amplifiers for high-frequency electrical signals, used to detect local brainwaves, for example, as their compact design means many of the devices can be connected in series. www.unibas.ch/en. PROBING SEMICONDUCTING CRYSTALS Tohoku University, Japan, re- searchers improved a method that uses omnidirectional photolumines- cence (ODPL) spectroscopy to probe for defects and impurities in semiconduct- ing crystals. The enhanced technique could help advance the fabrication of materials for electric cars and solar cells. The team demonstrated their approach using gallium nitride crystals, TESTING | CHARACTERIZATION 3D-PRINTED METAL BEHAVIOR Researchers from the University Carlos III of Madrid are analyzing micro- scopic pores in 3D-printed metals to better understand how these ductile materials fracture. According to the researchers, they have “identified how the microvoids or intrinsic micropores in the material grow, shrink, and inter- act with each other by accelerating or delaying the fracture of this mate- rial, depending on the viscosity of the material, the speed at which the load is applied to the material, and the loading path.” Advances in this field improve understanding of how 3D-printed duc- tile metals behave and will help design and manufacture sturdier parts and components in a variety of industries. The new SQUID is made up of a stack of two-dimensional materials, including two graphene layers separated by a thin film of boron nitride. Courtesy of University of Basel, Department of Physics. These materials can be used in processes where energy absorption is important, such as in the manufac- ture of new fuselages in the aerospace industry, different car parts in the automotive industry, or for developing implants in the biomedical industry. www.uc3m.es . DETECTING MAGNETIC FIELDS A miniscule instru- ment has been developed by physicists at the Univer- sity of Basel, Switzerland, to detect extremely faint mag- netic fields. Comprising the supercon- ducting quantum interference device, or SQUID, are two atomically thin lay- ers of graphene, which the research- ers combined with boron nitride. The team’s SQUID is one of the smallest to ever be built. Tomography reconstruction of a 3D-printed aluminum alloy manufactured (microvoids shown in orange). Courtesy of Universidad Carlos III de Madrid. The National Science Foundation awarded Binghamton University, N.Y., researchers a three-year grant to investigate a new method of producing microscopic circuits. The researchers will use carbon nanotubes to etch circuit patterns onto materials. binghamton.edu . BRIEF