Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Understanding tiny reactions

Launched laser-cooled atoms are captured by a single, suspended, single-wall carbon nanotube charged to hundreds of volts. A captured atom spirals toward the nanotube (white path) and reaches the environs of the tube surface, where its valence electron (yellow) tunnels into the tube. The resulting ion (purple) is ejected and detected, and the dynamics at the nanoscale are sensitively probed. Credit: Anne Goodsell and Tommi Hakala/Harvard University
Launched laser-cooled atoms are captured by a single, suspended, single-wall carbon nanotube charged to hundreds of volts. A captured atom spirals toward the nanotube (white path) and reaches the environs of the tube surface, where its valence electron (yellow) tunnels into the tube. The resulting ion (purple) is ejected and detected, and the dynamics at the nanoscale are sensitively probed. Credit: Anne Goodsell and Tommi Hakala/Harvard University

Abstract:
Cold atoms and nanotubes come together in atomic 'black hole'

By Steve Bradt, Harvard Staff Writer

Understanding tiny reactions

Cambridge, MA | Posted on April 8th, 2010

Carbon nanotubes, long touted for applications in electronics and in materials, may also be the stuff of atomic-scale black holes.

Physicists at Harvard University have found that a high-voltage nanotube (a tiny tubelike structure) can cause cold atoms to spiral inward under dramatic acceleration before disintegrating violently. The physicists' experiments, which are the first to demonstrate something akin to a black hole at atomic scale, are described in the current issue of the journal Physical Review Letters.

"On a scale of nanometers, we create an inexorable and destructive pull similar to what black holes exert on matter at cosmic scales," said Lene Vestergaard Hau, Mallinckrodt Professor of Physics and of Applied Physics at Harvard. "As importantly for scientists, this is the first merging of cold atom and nanoscale science, and it opens the door to a new generation of cold atom experiments and nanoscale devices."

Hau and co-authors Anne Goodsell, Trygve Ristroph, and Jene A. Golovchenko laser-cooled clouds of 1 million rubidium atoms to just a fraction of a degree above absolute zero. The physicists then launched this millimeter-long atomic cloud toward a suspended carbon nanotube, located some two centimeters away and charged to hundreds of volts.

The vast majority of the atoms passed right by the wire, but those that came within a micron of it — roughly 10 atoms in every million-atom cloud — were inescapably attracted, reaching high speeds as they spiraled toward the nanotube.

"From a start at about 5 meters per second, the cold atoms reach speeds of roughly 1,200 meters per second, or more than 2,700 miles per hour, as they circle the nanotube," said Goodsell, a graduate student on the project and now a postdoctoral researcher in physics at Harvard. "As part of this tremendous acceleration, the temperature corresponding to the atoms' kinetic energy increases from 0.1 degrees Kelvin to thousands of degrees Kelvin in less than a microsecond."

At this point, the speeding atoms separate into an electron and an ion rotating in parallel around the nanowire, completing each orbit in just a few trillionths of a second. The electron eventually gets sucked into the nanotube via quantum tunneling, causing its companion ion to shoot away — repelled by the strong charge of the 300-volt nanotube — at a speed of roughly 26 kilometers per second, or 59,000 miles per hour.

The experiment was conducted with great precision, allowing the scientists unprecedented access to both cold atom and nanoscale processes.

"Cold atom and nanoscale science have each provided exciting new systems for study and applications," said Golovchenko, Rumford Professor of Physics and Gordon McKay Professor of Applied Physics at Harvard. "This is the first experimental realization of a combined cold atom-nanostructure system. Our system demonstrates sensitive probing of atom, electron, and ion dynamics at the nanoscale."

The single-walled carbon nanotube used in these researchers' successful experiment was dubbed "Lucy," and its contributions are acknowledged in the Physical Review Letters paper. The nanotube was grown by chemical vapor deposition across a 10-micron gap in a silicon chip that provides the nanowire with both mechanical support and electrical contact.

"From the atom's point of view, the nanotube is infinitely long and thin, creating a singular effect on the atom," Hau said.

The work was supported by the Air Force Office of Scientific Research and the National Science Foundation.

####

For more information, please click here

Copyright © Harvard University

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Creating a color printer that uses a colorless, non-toxic ink inspired by nature February 11th, 2016

SLAC X-ray laser turns crystal imperfections into better images of important biomolecules: New method could remove major obstacles to studying structures of complex biological machines February 11th, 2016

Nanoparticle reduces targeted cancer drug's toxicity February 11th, 2016

Cima NanoTech Debuts Large Interactive Touch Screens with European Customers at ISE 2016: For the first time in Europe, Cima NanoTech’s wide range of high performance, projected capacitive touch modules are showcased February 11th, 2016

Govt.-Legislation/Regulation/Funding/Policy

Creating a color printer that uses a colorless, non-toxic ink inspired by nature February 11th, 2016

SLAC X-ray laser turns crystal imperfections into better images of important biomolecules: New method could remove major obstacles to studying structures of complex biological machines February 11th, 2016

Composite Pipe Long Term Testing Facility February 10th, 2016

Scientists take nanoparticle snapshots February 10th, 2016

Academic/Education

SUNY Poly and GLOBALFOUNDRIES Announce New $500M R&D Program in Albany To Accelerate Next Generation Chip Technology: Arrival of Second Cutting Edge EUV Lithography Tool Launches New Patterning Center That Will Generate Over 100 New High Tech Jobs at SUNY Poly February 9th, 2016

COD Grad Begins Postdoctoral Fellow at Harvard University: Marsela Jorgolli's Passion for Physics Has Led to a Decade of Academic Research That Continues at Harvard University as a Postdoctoral Fellow February 2nd, 2016

Heriot-Watt's Institute of Photonics & Quantum Sciences uses the Deben Microtest 2 kN tensile stage to characterise ceramics and engineering plastics January 21st, 2016

Multiple uses for the JPK NanoWizard AFM system in the Smart Interfaces in Environmental Nanotechnology Group at the University of Illinois at Urbana-Champaign January 20th, 2016

Nanotubes/Buckyballs/Fullerenes

Superconductivity: Footballs with no resistance - Indications of light-induced lossless electricity transmission in fullerenes contribute to the search for superconducting materials for practical applications February 9th, 2016

The iron stepping stones to better wearable tech without semiconductors February 8th, 2016

Nano-coating makes coaxial cables lighter: Rice University scientists replace metal with carbon nanotubes for aerospace use January 28th, 2016

Scientists provide new guideline for synthesis of fullerene electron acceptors January 28th, 2016

Discoveries

Creating a color printer that uses a colorless, non-toxic ink inspired by nature February 11th, 2016

SLAC X-ray laser turns crystal imperfections into better images of important biomolecules: New method could remove major obstacles to studying structures of complex biological machines February 11th, 2016

Nanoparticle reduces targeted cancer drug's toxicity February 11th, 2016

Chemical cages: New technique advances synthetic biology February 10th, 2016

Announcements

Creating a color printer that uses a colorless, non-toxic ink inspired by nature February 11th, 2016

SLAC X-ray laser turns crystal imperfections into better images of important biomolecules: New method could remove major obstacles to studying structures of complex biological machines February 11th, 2016

Nanoparticle reduces targeted cancer drug's toxicity February 11th, 2016

Cima NanoTech Debuts Large Interactive Touch Screens with European Customers at ISE 2016: For the first time in Europe, Cima NanoTech’s wide range of high performance, projected capacitive touch modules are showcased February 11th, 2016

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic