Tag Archives: wavelengths

New Technique Controls Dimensions of Gold Nanorods while Manufacturing on a Large Scale

North Carolina State University researchers have a developed a technique for efficiently producing nanoscale gold rods in large quantities while simultaneously controlling the dimensions of the nanorods and their optical properties. The optical properties of gold nanorods make them desirable for use in biomedical applications ranging from imaging technologies to cancer treatment.

“This technique should facilitate the economical manufacture of large volumes of gold nanorods,” says Dr. Joseph Tracy, an associate professor of materials science and engineering at NC State and senior author of a paper on the work. “And that should be good news for both the science community and the biomedical research and development community.” (more…)

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Researchers ‘Nanoweld’ by Applying Light to Aligned Nanorods in Solid Materials

Researchers from North Carolina State University have developed a way to melt or “weld” specific portions of polymers by embedding aligned nanoparticles within the materials. Their technique, which melts fibers along a chosen direction within a material, may lead to stronger, more resilient nanofibers and materials.

Physicists Jason Bochinski and Laura Clarke, with materials scientist Joe Tracy, placed specifically aligned gold nanorods within a solid material. Gold nanorods absorb light at different wavelengths, depending upon the size and orientation of the nanorod, and then they convert that absorbed light directly into heat. In this case, the nanorods were designed to respond to light wavelengths of 520 nanometers (nm) in a horizontal alignment and 800 nm when vertically aligned. Human beings can see light at 520 nm (it looks green), while 808 nm is in the near infrared spectrum, invisible to our eyes. (more…)

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Researchers Develop New Amp to Study the Universe

Researchers at NASA’s Jet Propulsion Laboratory and the California Institute of Technology, both in Pasadena, have developed a new type of amplifier for boosting electrical signals. The device can be used for everything from studying stars, galaxies and black holes to exploring the quantum world and developing quantum computers.

“This amplifier will redefine what it is possible to measure,” said Jonas Zmuidzinas, chief technologist at JPL, who is Caltech’s Merle Kingsley Professor of Physics and a member of the research team. (more…)

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Lighting the Way to a Fast, Low-power Optical Transistor

COLLEGE PARK, Md. — There has been enormous progress in recent years toward the ability to use light beams instead of, or together with, electrons in computers. Now, researchers at the Joint Quantum Institute (JQI) — a University of Maryland-based collaboration between UMD and the National Institutes of Standards and Technology — have developed a light-based switch that is a major advance toward the creation of an optical equivalent of the transistor, the centerpiece of most electronic gear.

UMD and JQI scientist Ranojoy Bose, says their new optical switch is not quite an optical transistor yet, but that their new results — which will be published in an upcoming issue of the journal Physical Review Letters
— represent a great start toward creating a usable ultrafast, low-energy on-chip signal router. “Our paper shows that switching can be achieved physically by using only 6 photons of energy, which is completely unprecedented. This is the achievement of fundamental physical milestonessub-100-aJ switching and switching near the single photon level,” Bose says (more…)

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You’re Beautiful, Vesta

NASA’s UCLA-led Dawn mission shows protoplanet’s surprising surface

When UCLA’s Christopher T. Russell looks at the images of the protoplanet Vesta produced by NASA’s Dawn mission, he talks about beauty as much as he talks about science.

“Vesta looks like a little planet. It has a beautiful surface, much more varied and diverse than we expected,” said Russell, a professor in UCLA’s Department of Earth and Space Sciences and the Dawn mission’s principal investigator. “We knew Vesta’s surface had some variation in color, but we did not expect the diversity that we see or the clarity of the colors and textures, or their distinct boundaries. We didn’t find gold on Vesta, but it is still a gold mine.”

Dawn has been orbiting Vesta and collecting data on the protoplanet’s surface since July 2011. Vesta, which is in the doughnut-shaped asteroid belt between Mars and Jupiter, is currently some 321 million miles from Earth. (more…)

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Planck All-Sky Images Show Cold Gas and Strange Haze

New images from the Planck mission show previously undiscovered islands of star formation and a mysterious haze of microwave emissions in our Milky Way galaxy. The views give scientists new treasures to mine and take them closer to understanding the secrets of our galaxy.

Planck is a European Space Agency mission with significant NASA participation. (more…)

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Scientists Prepare to Take First-Ever Picture of a Black Hole

*The Event Horizon Telescope is an Earth-sized virtual telescope powerful enough to see all the way to the center of our Milky Way, where a supermassive black hole will allow astrophysicists to put Einstein’s Theory of General Relativity to the test.*

Astronomers, physicists and scientists from related fields across the world will convene in Tucson, Ariz. on Jan. 18 to discuss an endeavor that only a few years ago would have been regarded as nothing less than outrageous.

The conference is organized by Dimitrios Psaltis, an associate professor of astrophysics at the University of Arizona’s Steward Observatory, and Dan Marrone, an assistant professor of astronomy at Steward Observatory. (more…)

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