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Patches of chain-like molecules placed across nanoscale particles can radically transform the optical, electronic, and magnetic properties of particle-based materials. Understanding why depends critically on the three-dimensional features of these “polymer nano-patches”—which are tantalizingly difficult to reveal at a scale spanning just billionths of a meter.

Now, scientists have used cutting-edge electron tomography techniques—a process of 3D reconstructive imaging —to pinpoint the structure and composition of the polymer nano-patches. The results, published earlier this month in the journal Nature, “lay the foundation for new nanoscale architectures that could potentially enhance technologies such as self-assembled solar cells and catalysts,” said lead author Eugenia Kumacheva of the University of Toronto.

The scientists tracked the patches formed by different synthetic polymers—versatile and common compounds used in everything from plastics to electronics —on the surface of gold nanospheres thousands of times smaller than the width of a single human hair. To visualize the elusive surface structures, Kumacheva and her team turned to cutting-edge facilities at the Center for Functional Nanomaterials (CFN), a U.S. Department of Energy (DOE) Office of Science User Facility at DOE’s Brookhaven National Laboratory.

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Extremely accurate measurements of microwave signals can potentially be used for data encryption based on quantum cryptography and other purposes.

Researchers at Aalto University and the University of Jyväskylä have developed a new method of measuring extremely accurately. This method can be used for processing quantum information, for example, by efficiently transforming signals from microwave circuits to the optical regime.

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In the TU Wien design, quantum cascade heterostructures are arrayed within concentric ring-shaped waveguides (top; diameter of outer ring is 400 microns), and can act as both sources and detectors of light on the same chip. In the specific setup tested by the lab (bottom), one of the ring structures (on the right), acting in QCL mode, sends its light through a chamber containing the gas to be analyzed. The beam is reflected by a mirror (on the left) and sent back through the chamber, to be picked up by the other ring structure, acting in detector mode. [Image: TU Wien]

Quantum cascade lasers (QCL) excel as mid-infrared light sources, a characteristic that has made them a linchpin in many environmental and industrial gas-sensing applications. But though QCLs themselves can be quite small, actually setting up a sensor system requires other elements beyond the laser, which can make it tough to design compact devices ready for field use.

A team of scientists from the Vienna University of Technology (TU Wien), Austria, now offers a concept that the group believes could make designing handheld QCL-based sensors a lot easier. The key: a clever scheme that combines the laser and the detector on a single chip less than half a millimeter across (ACS Photon., doi: 10.1021/acsphotonics.6b00603).

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Ready to leave your body behind? Scientists have developed robots that people can remotely control and embody using their minds, a breakthrough set to revolutionize the lives of paralyzed patients. The Virtual Embodiment and Robotic Re-Embodiment (VERE) project “aims at dissolving the boundary between the human body and surrogate representations in immersive virtual reality and physical reality,” meaning that people genuinely feel like the surrogate body is an extension of themselves. Three volunteers have tried out a prototype, and the results are promising.

“The feeling of actually embodying the robot was good, although needless to say, the sensation varied over time,” said Alessandro, a volunteer on the project, in an interview published Wednesday. “When the robot was stationary, the feeling of embodiment was low, but the moment I gave the first command or changed direction, there was this feeling of control and increased embodiment.”

The three volunteers, based in Italy, placed an electroencephalogram (EEG) cap on their heads that scanned for brain activity through the scalp. Patients were given a video feed of what a robot in Japan could see, superimposed with arrows. When the wearer focused on one arrow, the machine was able to detect the signal and send it remotely to the robot.

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Abstract: In 1959 renowned physicist Richard Feynman, in his talk “Plenty of Room at the Bottom,” spoke of a future in which tiny machines could perform huge feats. Like many forward-looking concepts, his molecule and atom-sized world remained for years in the realm of science fiction.

And then, scientists and other creative thinkers began to realize Feynman’s nanotechnological visions.

In the spirit of Feynman’s insight, and in response to the challenges he issued as a way to inspire scientific and engineering creativity, electrical and computer engineers at UC Santa Barbara have developed a design for a functional nanoscale computing device. The concept involves a dense, three-dimensional circuit operating on an unconventional type of logic that could, theoretically, be packed into a block no bigger than 50 nanometers on any side.

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