Bright Ideas: 10/13/21 — U.S. Gets First Open-Access Silicon Carbide Fabrication Facility, Light Produced From "Nothing"
By Abby Proch, former editor
In defense news, L3Harris Technologies secured a $18.4 million contract for MK 20 electro-optical sensor systems (EOSS) and radar cross section kits, as well as other supporting technologies and engineering services, according to a DoD contract announcement. L3 Harris says the MK 20 EOSS is an affordable, multi-purpose electro-optical sensor system that provides Naval Gun Weapon System (GWS) targeting, surveillance, and situational awareness. The MK 20 EOSS is currently used onboard a Navy destroyer, Navy cruiser, and Coast Guard offshore patrol cutters. The contract has an option for additional work that would bring the cumulative contract total to $54.2 million. The work is expected to be complete by September 2024.
When it comes to vision, scientists have long considered that the brain determines a stabilized visual field by capturing data moments before and after — but not necessarily during — eye movement. But now, scientists understand that the visual field is also created by what they call “motion streaks,” which offer less-rich visual data collected during eye movement. According to Science.org, scientists Richard Schweitzer and Martin Rolfs used a high-speed projector to guide participants’ eyes toward a particular target, tracking their movement along the way. They noted that the participants’ eyes used “motion streaks” to follow the target. When they adjusted the targets and removed the motion streaks, participants’ eyes “landed” on an incorrect target more often. With this discovery, the pair believe this newfound knowledge is key in advancing machine vision and robotics, not to mention ophthalmic care.
A $17.9 million grant from the National Science Foundation will help establish the first open-access silicon carbide fabrication facility in the United States. According to a University of Arkansas press release, the NSF awarded the funds to the university and a team of engineers led by Professor Alan Mantooth to create a center that will research and produce integrated circuits made with silicon carbide (a semiconductor suited to high temperatures), which in turn will reduce U.S. dependence on international suppliers. Currently, domestic silicon carbide is solely produced for internal use at private firms.
“The national impact of having a fabrication facility such as this is enormous,” Mantooth said in the release. “The country that leads the world in advancing silicon carbide semiconductor design and fabrication will also lead the race to market nearly all new game-changing technologies, including those used by the military, as well as general electronic devices that are essential to our economy.”
The NSF funding will provide updated equipment and technologies as well as additional staffing.
Once thought unobservable, even impossible, light produced from “nothing” may now be a reality, according to researchers at Dartmouth College. Distinguished Professor Miles Blencowe and his team, funded by the NSF, have developed a theoretical method after conducting an experiment in which they set a suspended manufactured diamond membrane with multiple accelerating photon detectors inside a vacuum. When the membrane oscillated at massive rates, photons were produced.
“In essence, all you need to do is shake something violently enough to produce entangled photons,” said postdoctoral researcher Hui Wang in the university press release.
Researchers say this observation could help improve understanding of the science behind black holes and quantum physics.
With a little finesse, chalcogenide glasses may now be used in visible and ultraviolet light, opening themselves up to applications in underwater communications, environmental monitoring, and biological imaging, according a report in ScienceDaily. Chalcogenide glasses are a class of glass containing chalcogens such as sulfur, selenium, and tellurium, but not oxygen, and are typically reserved for use in the near- and mid-infrared spectrum. However, in this experiment, researchers applied a thin film of arsenic trisulfide onto glass, nanostructured it using electron beam lithography and reactive ion etching, and produced nanowires 430 nm thick spaced 625 nm apart.
Illuminated with near-IR light, the arsenic trisulfide nanowires generated and transmitted at their original frequency – and their third harmonic. Usually, arsenic trisulfide absorbs light above 600 THz, which is about the color of cyan. But in this instance, the nanowires transmitted small signals at 846 THz, just above the 800 THz threshold to fall in the UV spectrum. Next up for the team is testing shape other than the nanowire to elicit the best output.
Glow-in-the-dark materials are fun and functional, but organic luminophores can be unrealistic in application and synthetic luminophores can be harmful to the environment. Now, researchers at Northeast Forestry University (China) and the University of Bath (UK) say they’re developing phosphorescent materials made from lignin, a component of wood. They’ve studied basswood and have found that when lignin is stabilized in a 3D matrix of poly(acrylic) acid and excited with UV light, the material glows long enough (100 milliseconds) to be visible to the naked eye. This substantial afterglow means that the material could be used to create flexible afterglow RTF (room temperature phosphorescence) fibers. Those fibers could be integrated into fabric as a characteristic to help scrutinize paper money and luxury items, such as purses, for authenticity.