Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists use microscope to view magnetism at atomic level

07.11.2002



Scientists and engineers build the transistors that run televisions, radios and similar electronic devices based on the moving electric charges of electrons. But the electron also has another key property: a magnetic "spin" that scientists believe could be exploited to develop faster, smaller and more efficient devices.

The first step is to determine the magnetic properties of materials that could be used to create futuristic nanoscale devices, a task that has escaped scientists until now. But research published online November 6 in the journal Physical Review Letters by a team of Ohio University physicists details a technique for measuring magnetism at the atomic scale using a scanning tunneling microscope.

Physicists Arthur Smith and Haiqiang Yang employed the high-powered microscope to explore the magnetic properties of a new crystalline compound comprised of manganese and nitrogen, which has potential use in future electronic or magnetic devices.



"It’s the best technique we have for measuring magnetic structure at the atomic scale," said Smith, whose project is funded by the National Science Foundation.

In a device that employs both electronics and "spintronics," a thin layer of magnetic material would be added to conventional electronics to improve performance. Possible applications include a spintronics LED for computer screens, more powerful hard drives and the quantum computer, which could make it possible to perform certain types of complex calculations which would be virtually impossible using conventional computers, said Smith, an assistant professor of physics and astronomy.

"These devices are so rare, so far in the future, that people have only begun to think about what to use them for," he said.

One obstacle scientists face is making the scientific process behind such experimental devices work at room temperature. Current devices work at cold temperatures, typically at or below minus 320 degrees Fahrenheit.

Smith and Yang, a postdoctoral researcher at Ohio University, have been studying the properties of the crystalline compound of manganese and nitrogen for two years, as it has the potential to function at room temperature, Yang said. In the recent experiment, the scientists coated the tip of a needle with magnetized atoms. Then, using it in their microscope like the needle of a record player to "read" the recorded information of a tiny surface area, they observed the magnetic poles of some rows of atoms pointing in one direction, and the poles of other rows of atoms pointing in the opposite direction. On non-magnetic surfaces, the atoms do not have oriented magnetic poles.

Other scientists have had little success using other techniques – which are too indirect or lack the necessary sensitivity -- to image magnetic spin at the atomic level. This suggests that the spin-polarized scanning tunneling microscope holds promise for research in this area, Smith said.

"Our paper provides new evidence that this technique works and that it’s a very important technique for nanotechnology," he said.

Nanomagnetism is a growing area of nanotechnology, Smith said, and scientists in the field expect to begin building nanoscale magnetic structures in the next two years. Now that the physicists have been able to measure spin at the nanoscale, Yang added, they also hope to use the scanning tunneling microscope to modify the surface of magnetic compounds.

Collaborators on the paper are Margarita Prikhodko and Walter Lambrecht of Case Western Reserve University.

Andrea Gibson | EurekAlert!
Further information:
http://www.ohio.edu/researchnews/
http://prl.aps.org/

More articles from Physics and Astronomy:

nachricht Four elements make 2-D optical platform
26.09.2017 | Rice University

nachricht The material that obscures supermassive black holes
26.09.2017 | Instituto de Astrofísica de Canarias (IAC)

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The fastest light-driven current source

Controlling electronic current is essential to modern electronics, as data and signals are transferred by streams of electrons which are controlled at high speed. Demands on transmission speeds are also increasing as technology develops. Scientists from the Chair of Laser Physics and the Chair of Applied Physics at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have succeeded in switching on a current with a desired direction in graphene using a single laser pulse within a femtosecond ¬¬ – a femtosecond corresponds to the millionth part of a billionth of a second. This is more than a thousand times faster compared to the most efficient transistors today.

Graphene is up to the job

Im Focus: LaserTAB: More efficient and precise contacts thanks to human-robot collaboration

At the productronica trade fair in Munich this November, the Fraunhofer Institute for Laser Technology ILT will be presenting Laser-Based Tape-Automated Bonding, LaserTAB for short. The experts from Aachen will be demonstrating how new battery cells and power electronics can be micro-welded more efficiently and precisely than ever before thanks to new optics and robot support.

Fraunhofer ILT from Aachen relies on a clever combination of robotics and a laser scanner with new optics as well as process monitoring, which it has developed...

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Nerves control the body’s bacterial community

26.09.2017 | Life Sciences

Four elements make 2-D optical platform

26.09.2017 | Physics and Astronomy

Goodbye, login. Hello, heart scan

26.09.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>