Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International

Wikipedia Affiliate Button

Home > Press > Stanford writes in world's smallest letters: Storing information in electron waves

This is an electron wave quantum hologram displaying the initials "SU" of Stanford University. The yellow area is a copper surface. The holes in the copper are molecules of carbon monoxide. Constantly moving electrons on the surface of the copper bounce off the carbon monoxide molecules in predictable ways. With their dual wave/particle properties, the electron waves in the purple area create inference patterns that can store readable information, in this case, SU. To store information, the researchers arrange the molecule in specific patterns with a scanning tunneling microscope.

Credit: Stanford University
This is an electron wave quantum hologram displaying the initials "SU" of Stanford University. The yellow area is a copper surface. The holes in the copper are molecules of carbon monoxide. Constantly moving electrons on the surface of the copper bounce off the carbon monoxide molecules in predictable ways. With their dual wave/particle properties, the electron waves in the purple area create inference patterns that can store readable information, in this case, SU. To store information, the researchers arrange the molecule in specific patterns with a scanning tunneling microscope.

Credit: Stanford University

Abstract:
Stanford researchers have reclaimed bragging rights for creating the world's smallest writing, a distinction the university first gained in 1985 and lost in 1990.

How small is the writing? The letters in the words are assembled from subatomic sized bits as small as 0.3 nanometers, or roughly one third of a billionth of a meter.

Stanford writes in world's smallest letters: Storing information in electron waves

Palo Alto, CA | Posted on January 31st, 2009

The researchers encoded the letters "S" and "U" (as in Stanford University) within the interference patterns formed by quantum electron waves on the surface of a sliver of copper. The wave patterns even project a tiny hologram of the data, which can be viewed with a powerful microscope.

"We miniaturized their size so drastically that we ended up with the smallest writing in history," said Hari Manoharan, the assistant professor of physics who directed the work of physics graduate student Chris Moon and other researchers.

The quest for small writing has played a role in the development of nanotechnology for 50 years, beginning decades before "nano" became a household word. During a now-legendary talk in 1959, the remarkable physicist Richard Feynman argued that there were no physical barriers preventing machines and circuitry from being shrunk drastically. He called his talk "There's Plenty of Room at the Bottom."

Feynman offered a $1,000 prize for anyone who could find a way to rewrite a page from an ordinary book in text 25,000 times smaller than the usual size (a scale at which the entire contents of the Encyclopedia Britannica would fit on the head of a pin). He held onto his money until 1985, when he mailed a check to Stanford grad student Tom Newman, who, working with electrical engineering Professor Fabian Pease, used electron beam lithography to engrave the opening page of Dickens' A Tale of Two Cities in such small print that it could be read only with an electron microscope.

That record held until 1990, when researchers at a certain computer company famously spelled out the letters IBM by arranging 35 individual xenon atoms.

Now, in a paper published online in the journal Nature Nanotechnology, the Stanford researchers describe how they have created letters 40 times smaller than the original prize-winning effort and more than four times smaller than the IBM initials. (www.youtube.com/watch?v=j3QQJEHuefQ)

Working in a vibration-proof basement lab in the Varian Physics Building, Manoharan and Moon began their writing project with a scanning tunneling microscope, a device that not only sees objects at a very small scale but also can be used to move around individual atoms. The Stanford team used it to drag single carbon monoxide molecules into a desired pattern on a copper chip the size of a fingernail.

On the two-dimensional surface of the copper, electrons zip around, behaving as both particles and waves, bouncing off the carbon monoxide molecules the way ripples in a shallow pond might interact with stones placed in the water.

The ever-moving waves interact with the molecules and with each other to form standing "interference patterns" that vary with the placement of the molecules.

By altering the arrangement of the molecules, the researchers can create different waveforms, effectively encoding information for later retrieval. To encode and read out the data at unprecedented density, the scientists have devised a new technology, Electronic Quantum Holography.

In a traditional hologram, laser light is shined on a two-dimensional image and a ghostly 3-D object appears. In the new holography, the two-dimensional "molecular holograms" are illuminated not by laser light but by the electrons that are already in the copper in great abundance. The resulting "electronic object" can be read with the scanning tunneling microscope.

Several images can be stored in the same hologram, each created at a different electron wavelength. The researchers read them separately, like stacked pages of a book. The experience, Moon said, is roughly analogous to an optical hologram that shows one object when illuminated with red light and a different object in green light.

For Manoharan, the true significance of the work lies in storing more information in less space. "How densely can you encode information on a computer chip? The assumption has been that basically the ultimate limit is when one atom represents one bit, and then there's no more room—in other words, that it's impossible to scale down below the level of atoms.

"But in this experiment we've stored some 35 bits per electron to encode each letter. And we write the letters so small that the bits that comprise them are subatomic in size. So one bit per atom is no longer the limit for information density. There's a grand new horizon below that, in the subatomic regime. Indeed, there's even more room at the bottom than we ever imagined."

In addition to Moon and Manoharan, authors of the Nature Nanotechnology paper, "Quantum Holographic Encoding in a Two-Dimensional Electron Gas," are graduate students Laila Mattos, physics; Brian Foster, electrical engineering; and Gabriel Zeltzer, applied physics.

The research was supported by the Department of Energy through SLAC National Accelerator Laboratory and the Stanford Institute for Materials and Energy Science (SIMES), the Office of Naval Research, the National Science Foundation and the Stanford-IBM Center for Probing the Nanoscale.

####

For more information, please click here

Contacts:
Dan Stober

650-721-6965

Copyright © Stanford 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 Links

Video: The World's Smallest Writing

Stanford News Service story: Reading the fine print takes on a new meaning

MANOHARAN LAB

RICHARD FEYNMAN'S 1959 NANOTECHNOLOGY TALK

NATURENEWS STORY

Related News Press

News and information

Let the europium shine brighter January 21st, 2020

Nanotubes may give the world better batteries: Rice U. scientists' method quenches lithium metal dendrites in batteries that charge faster, last longer January 16th, 2020

Quantum physics: Controlled experiment observes self-organized criticality January 16th, 2020

Pretty with a twist: Complex porous, chiral nano-patterns arise from a simple linear building block January 16th, 2020

Videos/Movies

Scientists develop gentle, microscopic hands to study tiny, soft materials December 23rd, 2019

Tiny magnetic particles enable new material to bend, twist, and grab December 13th, 2019

'Buildings' in human bone may hold key to stronger 3D-printed lightweight structures December 6th, 2019

‘Epidermal VR’ gives technology a human touch: Thin, flexible skin-interfaced system has applications in social interactions, prosthetics, telemedicine and entertainment November 21st, 2019

Govt.-Legislation/Regulation/Funding/Policy

Study finds billions of quantum entangled electrons in 'strange metal' Physicists provide direct evidence of entanglement's role in quantum criticality January 16th, 2020

Pretty with a twist: Complex porous, chiral nano-patterns arise from a simple linear building block January 16th, 2020

Toward safer disposal of printed circuit boards January 16th, 2020

Researchers gain control over internal structure of self-assembled composite materials January 16th, 2020

Academic/Education

Matching Investment Program (MIP) Leverages $140K Empire State Development/NYSTAR Funding to SUNY Poly’s CATN2 to Enable $1.5M in Matching Commitments from Industry Partners: Investment Funds Faculty Research Related to Advanced Materials, Genomics, and Semiconductor Reliability October 18th, 2019

A Quantum Leap: $25M grant makes UC Santa Barbara home to the nation’s first NSF-funded Quantum Foundry, a center for development of materials for quantum information-based technologies September 16th, 2019

LPU signs MoU with Bruker India for Research Cooperation in Nanotechnology and Material Science September 3rd, 2019

RIT to upgrade Semiconductor and Microsystems Fabrication Laboratory through $1 million state grant: Upgrades to clean room will enhance university’s research capabilities in photonics, quantum technologies and smart systems August 16th, 2019

Discoveries

Let the europium shine brighter January 21st, 2020

Quantum physics: Controlled experiment observes self-organized criticality January 16th, 2020

Pretty with a twist: Complex porous, chiral nano-patterns arise from a simple linear building block January 16th, 2020

Toward safer disposal of printed circuit boards January 16th, 2020

Announcements

Let the europium shine brighter January 21st, 2020

Quantum physics: Controlled experiment observes self-organized criticality January 16th, 2020

Pretty with a twist: Complex porous, chiral nano-patterns arise from a simple linear building block January 16th, 2020

Toward safer disposal of printed circuit boards January 16th, 2020

Grants/Sponsored Research/Awards/Scholarships/Gifts/Contests/Honors/Records

Pretty with a twist: Complex porous, chiral nano-patterns arise from a simple linear building block January 16th, 2020

Gasification goes green: Rice's low-temp photocatalyst could slash the carbon footprint for syngas January 10th, 2020

Jill Tarter named 2019 Lifeboat Foundation Guardian Award Winner January 2nd, 2020

Scientists create thin films with tantalizing electronic properties: As predicted by theorists, experiments show that barium zirconium sulfide thin films hold great promise for solar cells, LEDs December 27th, 2019

Photonics/Optics/Lasers

Let the europium shine brighter January 21st, 2020

Nanotubes may give the world better batteries: Rice U. scientists' method quenches lithium metal dendrites in batteries that charge faster, last longer January 16th, 2020

CEA-Leti Will Present 21 Papers (Five Invited) at Photonics West 2020 & Host a Workshop January 9th, 2020

International Conference and Exhibition on Nanotechnology - Nano Seoul 2020 January 3rd, 2020

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



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project