Category Physics

(Photo by Elle Starkman) PPPL physicist Will Fox

Lasers that generate plasma can provide insight into bursts of subatomic particles that occur in deep space, scientists have found. Such findings could help scientists understand cosmic rays, solar flares and solar eruptions – emissions from the sun that can disrupt cell phone service and knock out power grids on Earth.

Physicists have long observed that particles like electrons and atomic nuclei can accelerate to extremely high speeds in space. Researchers believe that processes associated with plasma, the hot fourth state of matter in which electrons have separated from atomic nuclei, might be responsible...

Light on a CMOS chip. Credit: Image courtesy of University of Twente

Electronics and light don’t go well together on a standard ‘CMOS’ chip. Researcher Satadal Dutta of the University of Twente succeeded in introducing a light connection into the heart of a semiconductor chip. In this way, two circuits can communicate. Or: the worlds of electronics and photonics are connected.

What is particularly attractive about Dutta’s solution is that no special materials or manufacturing processes are needed: the light comes from silicon. The light source, detector and the light channel can be made using the technology that is used to make the electronic circuits...

A new pencil-like wireless spectrometer can be used with a smartphone to collect 3-D spectral images of the body and other objects. This design could make the device useful for point-of-care diagnostics. Credit: Dan Wang, Beijing University of Chemical Technology

Easy-to-use spectrometer less than $300, holds promise for remote medical diagnostics. A new smartphone-compatible device that is held like a pencil could make it practical to acquire spectral images of everyday objects and may eventually be used for point-of-care medical diagnosis in remote locations. Spectral images, which contain more color information than is obtainable with a typical camera, reveal characteristics of tissue and other biological samples that can’t be seen by the naked eye...

The Burton lab studies tiny, plastic particles as a model for more complex systems. The particles are suspended in a vacuum chamber filled with a plasma — ionized argon gas. Credit: Justin Burton, Emory University

Complex behavior emerges from a simple system in a fixed environment. Physicists at Emory University have shown how a system of lifeless particles can become “life-like” by collectively switching back and forth between crystalline and fluid states – even when the environment remains stable. “We’ve discovered perhaps the simplest physical system that can consistently keep changing behavior over time in a fixed environment,” says Justin Burton, Emory assistant professor of physics. “In fact, the system is so simple we never expected to see such a complex property emerge from it.”

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