“The textbook said we should see slow, gradual and random. But what we saw? BOOM! Fast, explosive and organized!” said Michael Tringides, physicist at the U.S. Department of Energy’s Ames Laboratory and a professor of physics and astronomy at Iowa State University.
Tringides is talking about the unusual atom movement he saw when they dropped a few thousand lead atoms onto a flat, smooth lead-on-silicon surface, all at low temperatures, and looked at an area just one-twentieth the width of a human hair.
What the Ames Laboratory scientists expected to see was “random-walk diffusion”: atoms milling around, looking like they have no idea where they’re going, where they’ve been, or that any fellow atoms are near them. Typically, the atoms eventually happen to run into each other and create small structures.
“Instead, we saw atoms that are very focused and work together well to quickly create tiny lead nanostructures,” said Tringides. “That kind of ‘collective diffusion,’ is really the exception to the rule in atom movement. Plus, we were surprised by how fast well-organized crystal structures nucleate at such cold temperatures, where movement is typically slow.”
The collective, fast diffusion observed by Tringides’ team could represent a new way to grow perfect, tiny metal nanostructures.
“If we’re able to make a nanoscale lead object this fast, we can perhaps create other objects this way.” said Tringides. “Understanding the basic science of how materials work at these nanoscales may be key to making nanotransistors, nanoswitches and nanomagnets smaller, faster and reliably.”
Tringides’ research team specializes in measuring how atoms move on surfaces, revealing through scanning tunneling microscopy how the smallest structures begin to form. Over the past several years, they’ve used their expertise to answer fundamental questions about materials, such as rare-earths, graphene and metallic films, that are important to green energy technologies.
This research, which appeared in Physical Review Letters, is supported by the U.S. Department of Energy Office of Science.
Ames Laboratory is a U.S. Department of Energy Office of Science national laboratory operated by Iowa State University. Ames Laboratory creates innovative materials, technologies and energy solutions. We use our expertise, unique capabilities and interdisciplinary collaborations to solve global problems.
DOE’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov
Breehan Gerleman Lucchesi
Breehan Gerleman Lucchesi | newswise
Researchers printed graphene-like materials with inkjet
18.08.2017 | Aalto University
Superconductivity research reveals potential new state of matter
17.08.2017 | DOE/Los Alamos National Laboratory
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
18.08.2017 | Life Sciences
18.08.2017 | Physics and Astronomy
18.08.2017 | Materials Sciences