Gizmorama - December 21, 2016

Good Morning,

Remember when we though cellular phones were getting too small? Now, scientists have built the world's smallest radio receiver. How does it sound?

Learn about this and more interesting stories from the scientific community in today's issue.

Until Next Time,
Erin

P.S. Did you miss an issue? You can read every issue from the Gophercentral library of newsletters on our exhaustive archives page. Thousands of issues, all of your favorite publications in chronological order. You can read AND comment. Just click GopherArchives



*-- Scientists build world's smallest radio receiver --*
CAMBRIDGE, Mass. - The building blocks of the world's smallest radio receiver consist of tiny defects in pink diamonds -- defects the size of two atoms.

The record-setting receiver was built by researchers at the Harvard John A. Paulson School of Engineering and Applied Sciences.

The man-made defects are called nitrogen-vacancy centers. Scientists replace a single carbon atom in a diamond with a nitrogen atom. A neighboring atom is removed entirely. The result is a nitrogen atom saddled next to a hole.

The most useful property of an NV center is photoluminescence. The centers convert information into light and can be manipulated by the application of a magnetic field, electric field, microwave radiation or light. The centers' photoluminescence can be utilized for quantum computing, bioimaging and other optical technologies.

Scientists at Harvard used the defects to build a radio receiver by exciting the centers with a green laser. The electrons expelled by the process are sensitive to electromagnetic fields, like radio waves. The radio waves impact the defect's electrons, causing the center to emit photons of red light. The red light is converted into electric current by a photodiode and into sound by a speaker.

An electromagnetic field surrounding the diamond can be manipulated to change the radio station by limiting the frequencies received by the nitrogen-vacancy centers.

The diamond's durability makes the radio resilient. Scientists successfully played music at temperatures upwards of 660 degrees Fahrenheit. Though multiple defects can be combined the produce a louder signal, the radio can also function using single laser photons fired into a solitary nitrogen-vacancy center.

"Diamonds have these unique properties," Marko Loncar, a professor a electrical engineering at Harvard, said in a news release. "This radio would be able to operate in space, in harsh environments and even the human body, as diamonds are biocompatible."

Researchers described their record-breaking radio in the journal Physical Review Applied.



*-- Rock painting helps scientists track erosion --*
POTSDAM, Germany - Scientists have struggled to measure the spatial distribution of erosive processes at intimate scales. Its difficult to set up the necessary instrumentation in harsh, rocky landscapes, and to devote the necessary amount of time for useful data collection.

Mostly, erosion is studied on large scales of time and space. But a new method developed by researchers at the GFZ German Research Centre for Geosciences offers a simpler way to visualize erosion -- rock painting.

In a proof-of-concept study, a trio of researchers from GFZ applied a vertical and horizontal patterns of paint to a total of 150 square meters of rock surface in the Swiss Alps. For three years, the scientists returned periodically to their paintings, taking photographs from the same variety of angles and distances.

The photographs can be used to measure the visual changes in the rock. Moved and removed paint revealed the spatial distribution of the riverbed's erosive processes. The scientists dubbed their analysis method "erosion painting."

"Using paint is a cheap and easy method to analyze the spatial distribution of erosive processes," researcher Jens Turowski said in a news release. "With this study we would like to show that this method can be applied for science."

Scientists conducted repeated laser scans to verify the validity of their new method. However, their laser scans weren't able to measure erosion in as fine of detail.

Researchers described their "erosion painting" method in the journal Earth Surface Dynamics.

***
Missed an Issue? Visit the Gizmorama Archives