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Researchers at the University of Ottawa have debunked the decade-old myth of metals being useless in photonics—the science and technology of light—with their findings, recently published in Nature Communications, expected to lead to many applications in the field of nanophotonics.

“We broke the record for the resonance quality factor (Q-factor) of a periodic array of by one order of magnitude compared to previous reports,” said senior author Dr. Ksenia Dolgaleva, Canada Research Chair in Integrated Photonics (Tier 2) and Associate Professor in the School of Electrical Engineering and Computer Science (EECS) at the University of Ottawa.

“It is a well-known fact that metals are very lossy when they interact with light, which means they cause the dissipation of electrical energy. The high losses compromise their use in optics and photonics. We demonstrated ultra-high-Q resonances in a metasurface (an artificially structured surface) comprised of an array of metal nanoparticles embedded inside a flat glass substrate. These resonances can be used for efficient light manipulating and enhanced light-matter interaction, showing metals are useful in photonics.”

If you want to build a fully functional nanosized robot, you need to incorporate a host of capabilities, from complicated electronic circuits and photovoltaics to sensors and antennas.

But just as importantly, if you want your robot to move, you need it to be able to bend.

Cornell researchers have created micron-sized shape memory actuators that enable atomically thin two-dimensional materials to fold themselves into 3D configurations. All they require is a quick jolt of voltage. And once the material is bent, it holds its shape—even after the voltage is removed.

At microscopic scales, picking, placing, collecting, and arranging objects is a persistent challenge. Advances in nanotechnology mean that there are ever more complex things we’d like to build at those sizes, but tools for moving their component parts are lacking.

Now, new research from the University of Pennsylvania’s School of Engineering and Applied Science shows how simple, microscopic robots, remotely driven by magnetic fields, can use capillary forces to manipulate objects floating at an oil-water interface.

This system was demonstrated in a study published in the journal Applied Physics Letters on January 28, 2020.

Transistors, devices that can amplify, conduct or switch electronic signals or electric current, are key components of many electronics on the market today. These devices can be fabricated using a variety of inorganic and organic semiconducting materials.

Metals are generally considered unsuitable for fabricating , as they screen electric fields and thus make it difficult to realize devices with tunable electrical conductivity. A possible way to create based on metals is to use gradients of counterions in films of metal nanoparticles functionalized with charged organic ligands.

In the past, engineers have successfully used this strategy to create a variety of devices, ranging from resistors to diodes and sensors. Nonetheless, modulating the electrical conductivity of these devices has often proved to be very challenging.

Study describes passive cooling system that aims to help impoverished communities, reduce cooling and heating costs, lower CO2 emissions.

Passive cooling, like the shade a tree provides, has been around forever.

Recently, researchers have been exploring how to turbo charge a passive cooling technique — known as radiative or sky cooling — with sun-blocking, nanomaterials that emit heat away from building rooftops. While progress has been made, this eco-friendly technology isn’t commonplace because researchers have struggled to maximize the materials’ cooling capabilities.

Today, machine learning permeates everyday life, with millions of users every day unlocking their phones through facial recognition or passing through AI-enabled automated security checks at airports and train stations. These tasks are possible thanks to sensors that collect optical information and feed it to a neural network in a computer.

Scientists in China have presented a new nanoscale AI trained to perform unpowered all-optical inference at the speed of light for enhanced authentication solutions. Combining smart optical devices with imaging sensors, the system performs complex functions easily, achieving a neural density equal to 1/400th that of the human brain and a more than 10 orders of magnitude higher than electronic processors.

Imagine empowering the sensors in everyday devices to perform artificial intelligence functions without a computer—as simply as putting glasses on them. The integrated holographic perceptrons developed by the research team at University of Shanghai for Science and Technology led by Professor Min Gu, a foreign member of the Chinese Academy of Engineering, can make that a reality. In the future, its neural density is expected to be 10 times that of human brain.

Imagine seeing the world in muted shades—gray sky, gray grass. Some people with color blindness see everything this way, though most can’t see specific colors. Tinted glasses can help, but they can’t be used to correct blurry vision. And dyed contact lenses currently in development for the condition are potentially harmful and unstable. Now, in ACS Nano, researchers report infusing contact lenses with gold nanoparticles to create a safer way to see colors.

The total amount of data generated worldwide is expected to reach 175 zettabytes (1 ZB equals 1 billion terabytes) by 2025. If 175 ZB were stored on Blu-ray disks, the stack would be 23 times the distance to the moon. There is an urgent need to develop storage technologies that can accommodate this enormous amount of data.