Featured Research

from universities, journals, and other organizations

Possible Computer Data Storage System Smaller Than A Dot On This Page Is Described By Cornell University Researchers

Date:
March 24, 1999
Source:
Cornell University
Summary:
Researchers at Cornell University are testing devices that could form the basis for a potential ultrasmall computer data storage system that could gather up to 100 times as much information in the same space as present-day magnetic data disks. An array of the devices that make up the system is considerably smaller than the period at the end of this sentence.

ATLANTA -- Researchers at Cornell University are testing devices that could form the basis for a potential ultrasmall computer data storage system that could gather up to 100 times as much information in the same space as present-day magnetic data disks. An array of the devices that make up the system is considerably smaller than the period at the end of this sentence.

Cornell postdoctoral associate Stephane Evoy and graduate students Lidija Sekaric and Dustin Carr described their work March 23 at the 1999 centennial meeting of the American Physical Society at the Georgia World Congress Center. They are part of a research group working under Harold Craighead, Cornell professor of applied and engineering physics, and Jeevak Parpia, Cornell professor of physics.

The devices are "nanomagnets"-- tiny bar magnets as small as 25 nanometers (nm) long. A nanometer is one billionth of a meter. Such nanomagnets are being considered by several research groups as potential candidates for future magnetic storage applications. However, to make a system based on nanomagnets work, designers have to learn some new physics.

Magnets less than about 100 nm wide have a unique property, Evoy said. When magnetized, each one forms a single magnetic "domain." That is, the magnetic fields of all the atoms in the magnet are perfectly aligned. In larger magnets, like the ones used to stick recipes to refrigerator doors, there are many smaller domains, or groups of atoms, aligned in various directions; the behavior of the magnet depends on how the majority of the domains are oriented.

Single-domain magnets, Evoy explained, could be used for data storage: A magnet could represent a one or a zero depending on which way its north and south poles pointed. The polarity could be changed by applying a magnetic field. But practical applications are still in the future. "We're not looking at the mechanisms for reading and writing to these devices as other groups are already addressing such issues," Evoy said. "What we need is to understand the physics of small magnets."

At the Cornell Nanofabrication Facility, the researchers deposited rows of tiny cobalt dots on silicon surfaces using techniques originally designed to make electronic circuits. In various experiments they created dots ranging from 25 nm to 100 nm wide, in several different arrangements. Most are about 80 nm wide, 140 nm long and about 20 nm thick.

The researchers have been able to read the orientation of individual magnets -- slowly -- using a magnetic force microscope (MFM). This is a device with a tiny tip suspended just above the surface to be examined. The tip is coated with a magnetic material and is scanned back and forth across the surface. The instrument records any magnetic interaction between the tip and the surface, forming a map of the distribution of magnetic fields.

In most experiments, the Cornell researchers apply a magnetic field to an entire array, then measure the states of the individual magnets with the MFM. They have found that there is a great deal of interaction between the tiny magnets. Sometimes, a whole row will line up one way, with adjacent rows in the opposite orientation. Sometimes changing the polarity of a single magnet will affect other magnets in its immediate vicinity, in all directions. This is particularly true when the spacing between the magnets is less than 400 nm, Evoy said.

To study the magnetic properties of large arrays of these nanomagnets, and the properties of silicon itself, Sekaric and Carr have built silicon oscillators consisting of small paddles about two to five microns wide, suspended at the ends by rods 50 nm to 100 nm thick. By applying an alternating-current electric field the researchers can cause the suspended surfaces to oscillate, something like a hammock in a high wind. With arrays of nanomagnets deposited on the paddles they will apply an external magnetic field and look for any change of the behavior of the paddle, which will give them information about the magnetic properties of the nanomagnet array.

The approach used to make these tiny oscillators could be used to make very sensitive magnetometers for the study of other magnetic systems, Sekaric said.

Related World Wide Web sites: The following sites provide additional information on this news release. Some might not be part of the Cornell University community, and Cornell has no control over their content or availability.

APS meeting program: http://www.aps.org/meet/CENT99/BAPS/

Craighead research group: http://www.hgc.cornell.edu


Story Source:

The above story is based on materials provided by Cornell University. Note: Materials may be edited for content and length.


Cite This Page:

Cornell University. "Possible Computer Data Storage System Smaller Than A Dot On This Page Is Described By Cornell University Researchers." ScienceDaily. ScienceDaily, 24 March 1999. <www.sciencedaily.com/releases/1999/03/990324062632.htm>.
Cornell University. (1999, March 24). Possible Computer Data Storage System Smaller Than A Dot On This Page Is Described By Cornell University Researchers. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/1999/03/990324062632.htm
Cornell University. "Possible Computer Data Storage System Smaller Than A Dot On This Page Is Described By Cornell University Researchers." ScienceDaily. www.sciencedaily.com/releases/1999/03/990324062632.htm (accessed October 21, 2014).

Share This



More Computers & Math News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Japanese Scientists Unveil Floating 3D Projection

Japanese Scientists Unveil Floating 3D Projection

Reuters - Innovations Video Online (Oct. 20, 2014) Scientists in Tokyo have demonstrated what they say is the world's first 3D projection that floats in mid air. A laser that fires a pulse up to a thousand times a second superheats molecules in the air, creating a spark which can be guided to certain points in the air to shape what the human eye perceives as an image. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Apple Enters Mobile Payment Business

Apple Enters Mobile Payment Business

AP (Oct. 20, 2014) Apple is making a strategic bet with the launch of Apple Pay, the mobile pay service aimed at turning your iPhone into your wallet. (Oct. 20) Video provided by AP
Powered by NewsLook.com
Apple Pay Goes Live

Apple Pay Goes Live

Reuters - Business Video Online (Oct. 20, 2014) Apple launches an ambitious new mobile service, Apple Pay, which aims to change the way consumers pay for goods and services, doing away with cash and traditional credit cards. Jeanne Yurman reports. Video provided by Reuters
Powered by NewsLook.com
Google To Protect Against Piracy ... At A Cost

Google To Protect Against Piracy ... At A Cost

Newsy (Oct. 20, 2014) Google is changing its search-engine results to protect content producers from piracy — for a price. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins