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“As complex living systems, we likely have trillions upon trillions of tiny nanoscopic holes in our cells that facilitate and regulate the crucial processes that keep us alive and make up who are,” says Marija Drndić, a physicist at the University of Pennsylvania who develops synthetic versions of the biological pores that “guide the exchange of ions and molecules throughout the body.”

The ability to control and monitor the flow of molecules through these pores has opened new avenues for research in the last two decades, according to Drndić, and the field of synthetic nanopores, where materials like graphene and silicon are drilled with tiny holes, has already led to significant advances in DNA sequencing.

In a paper published in Nature Nanotechnology (“Coupled nanopores for single-molecule detection”), Drndić and Dimitri Monos, her longtime collaborator at the Perelman School of Medicine and Children’s Hospital of Philadelphia (CHOP), presented a new kind of nanopore technology with the development of a dual-layer nanopore system: a design that consists of two or more nanopores, stacked just nanometers apart, which allows for more precise detection and control of molecules like DNA as they pass through.

As an innovative concept in materials science and engineering, the inspiration for self-healing materials comes from living organisms that have the innate ability to self-heal. Along this line, the search for self-healing materials has been generally focused on “soft” materials like polymers and hydrogels. For solid-state metals, one may intuitively imagine that any form of self-healing will be much more difficult to achieve.

Researchers at the Department of Instrumentation and Applied Physics (IAP), Indian Institute of Science (IISc) and collaborators have designed a new supercapacitor that can be charged by light shining on it. Such supercapacitors can be used in various devices, including streetlights and self-powered electronic devices such as sensors.

Capacitors are electrostatic devices that store energy as charges on two metal plates called electrodes. Supercapacitors are upgraded versions of capacitors—they exploit electrochemical phenomena to store more energy, explains Abha Misra, Professor at IAP and corresponding author of the study published in the Journal of Materials Chemistry A.

The electrodes of the new were made of (ZnO) nanorods grown directly on fluorine-doped tin oxide (FTO), which is transparent. It was synthesized by Pankaj Singh Chauhan, first author and CV Raman postdoctoral fellow in Misra’s group at IISc.

Now imagine a frequency mixer that works at a quadrillion (PHz, petahertz) times per second—up to a million times faster. This corresponds to the oscillations of the electric and magnetic fields that make up .

Petahertz-frequency mixers would allow us to shift signals up to and then back down to more conventional electronic frequencies, enabling the transmission and processing of vastly larger amounts of information at many times higher speeds. This leap in speed isn’t just about doing things faster; it’s about enabling entirely new capabilities.

Lightwave electronics (or petahertz electronics) is an emerging field that aims to integrate optical and electronic systems at incredibly high speeds, leveraging the ultrafast oscillations of light fields. The key idea is to harness the electric field of light waves, which oscillate on sub-femtosecond (10-15 seconds) timescales, to directly drive electronic processes.

Butterflies can see more of the world than humans, including more colors and the field oscillation direction, or polarization, of light. This special ability enables them to navigate with precision, forage for food and communicate with one another. Other species, like the mantis shrimp, can sense an even wider spectrum of light, as well as the circular polarization, or spinning states, of light waves. They use this capability to signal a “love code,” which helps them find and be discovered by mates.

Inspired by these abilities in the animal kingdom, a team of researchers at the Penn State College of Engineering has developed an ultrathin optical element known as a metasurface, which can attach to a conventional camera and encode the spectral and polarization data of images captured in a snapshot or video through tiny, antenna-like nanostructures that tailor light properties. A machine learning framework, also developed by the team, then decodes this multi-dimensional visual information in real-time on a standard laptop.

The researchers have published their work in Science Advances.