System Bits: Jan. 14

Integrated photonics platform
Researchers at Harvard’s John A. Paulson School of Engineering and Applied Sciences came up with an integrated photonics platform capable of storing light and electrically controlling its frequency or color through a microchip. Mian Zhang, first author of the resulting paper, says, “Many quantum photonic and classical optics applications require shifting of optical frequencies, which has been difficult. We show that not only can we change the frequency in a controllable manner, but using this new ability we can also store and retrieve light on demand, which has not been possible before.” Marko Loncar, the Tiantsai Lin Professor of Electrical Engineering, led the team that developed a technique to fabricate high-performance optical microstructures using lithium niobate, a material with powerful electro-optic properties. “The unique properties of lithium niobate, with its low optical loss and strong electro-optic nonlinearity, give us dynamic control of light in a programmable electro-optic system,” said Cheng Wang, co-first author of the paper and now Assistant Professor at City University of Hong Kong. “This could lead to the development of programmable filters for optical and microwave signal processing and will find applications in radio astronomy, radar technology, and more.”

A data processing alternative to the cloud
Queen’s University Belfast researchers report developing a system to process data geographically on a faster basis than uploading data to the computing cloud. The research team created an edge computing system to reduce delays in smart devices. Dr. Blesson Varghese of the Northern Ireland university’s Institute of Electronics, Communications and Information Technology says, “Edge computing offers a much faster solution for smart devices by bringing application services onto hardware that is geographically closer to users. This means that a proportion of the data can be processed there and doesn’t need to be sent all the way to the distant cloud. With the edge computing system we have designed, multiple traditionally cloud-hosted applications are able to service users from their adjacent places such as a home router. Consequently, delays experienced by application users are reduced. ECIT is leading the way in ensuring the adoption of edge computing. Our research focuses on developing the underlying approaches and software tools to deliver a comprehensive edge adoption solution. Our vision is to make the U.K. the first public adopters of edge computing.”

Ultra-sensitive sensor with gold nanoparticles
University of Bath researchers used a gold nanoparticle array to produce a sensor platform said to be much more sensitive than existing sensors. Composed of gold disk-shaped nanoparticles on a glass substrate, the sensor emitted unusual amounts of ultraviolet light after an infrared laser was directed at the particle array. This technology could have applications in ultra-sensitive sensors for air pollution and medical diagnostics. Ventsislav Valev, Royal Society Research Fellow and Reader in Physics at the University of Bath, led the work with Research Associate David Hooper. He said in a statement, “This new mechanism has great potential for detecting small molecules. It is 100 times more sensitive than current methods. The gold nanoparticle disks are arranged on a glass slide in a very precise array – changing the thickness and separation of the disks completely changes the detected signal. When molecules bind to the surface of a gold nanoparticle, they affect the electrons at the gold surface, causing them to change the amount of UV light they emit. The amount of UV light emitted would depend on the type of molecules that bind to the surface. This technique could enable ultra-sensitive detection of molecules in tiny volumes. It could in the future be used for detecting very low concentrations of biological markers for the early diagnostic screening for diseases, such as cancer.” The nanoparticles were fabricated by researchers at Northwestern University in Chicago, Illinois.

A battery-free, biodegradable blood-flow sensor
Stanford University researchers report developing a device that provides doctors with information on the results of blood vessel surgery. The sensor, which monitors the flow of blood through an artery, doesn’t need a battery, operates wirelessly, and is ultimately biodegradable. The compact device therefore doesn’t need to be removed from the patient. “Measurement of blood flow is critical in many medical specialties, so a wireless biodegradable sensor could impact multiple fields including vascular, transplant, reconstructive and cardiac surgery,” says Paige Fox, assistant professor of surgery and co-senior author of the paper. “As we attempt to care for patients throughout the Bay Area, Central Valley, California, and beyond, this is a technology that will allow us to extend our care without requiring face-to-face visits or tests.” The sensor is said to wrap around the healing blood vessel, making measurements on its inner surface. A paper detailing development of the sensor was published Jan. 8th in the Nature Biomedical Engineering journal.