Featured Research

from universities, journals, and other organizations

Einstein's Magnetic Effect Is Measured On Microscale

Date:
October 2, 2006
Source:
National Institute of Standards and Technology
Summary:
A gyromagnetic effect discovered by Albert Einstein and Dutch physicist Wander Johannes de Haas has been measured at micrometer-scale dimensions for the first time at the NIST. The new method may be useful in the development and optimization of thin film materials for read heads, memories and recording media for magnetic data storage and spintronics.

In NIST's Einstein-de Haas experiment, the movements of a cantilever were measured with an optical-fiber laser interferometer. The optical fiber is 125 micrometers in diameter, and the end is positioned less than 10 micrometers from the cantilever surface.
Credit: John Moreland/NIST

A gyromagnetic effect discovered by Albert Einstein and Dutch physicist Wander Johannes de Haas--the rotation of an object caused by a change in magnetization--has been measured at micrometer-scale dimensions for the first time at the National Institute of Standards and Technology (NIST). The new method may be useful in the development and optimization of thin film materials for read heads, memories and recording media for magnetic data storage and spintronics, an emerging technology that relies on the spin of electrons instead of their charge as in conventional electronics.

Related Articles


The Einstein-de Haas effect was first observed in experiments reported in 1915, in which a large iron cylinder suspended by a glass wire was made to rotate by an alternating magnetic field applied along the cylinder's central axis. By contrast, the NIST experiments, described in the Sept. 18 issue of Applied Physics Letters,* measured the Einstein-de Haas effect in a ferromagnetic thin film only 50 nanometers thick deposited on a microcantilever--a tiny beam anchored at one end and projecting into the air. An alternating magnetic field induced changes in the magnetic state of the thin film, and the resulting torque bent the cantilever up and down by just a few nanometers.

Using a laser interferometer to measure the movements of the cantilever and comparing those data to changes in the magnetic state of the material, researchers were able to determine the "magnetomechanical ratio," or the extent to which the material twists in response to changes in its magnetic state. The magnetomechanical ratio is related to another important parameter, the "g-factor," a measure of the internal magnetic rotation of the electrons in a material in a magnetic field.

The magnetomechanical ratio and the g-factor are critical in understanding magnetization dynamics and designing magnetic materials for data storage and spintronics applications, but they are extremely difficult to determine accurately because of many potential complicating effects. The NIST experiments provide a proof-of-concept for using the Einstein-de Haas effect to determine the magnetomechanical ratio and the related g-factor in thin ferromagnetic films. The researchers note that a number of improvements are possible, such as operating the cantilever system in a vacuum to reduce the effects of any changes in temperature.

* T.M. Wallis, J. Moreland and P. Kabos. 2006. Einstein-de Haas effect in a NiFe film deposited on a microcantilever. Applied Physics Letters. Sept. 18.


Story Source:

The above story is based on materials provided by National Institute of Standards and Technology. Note: Materials may be edited for content and length.


Cite This Page:

National Institute of Standards and Technology. "Einstein's Magnetic Effect Is Measured On Microscale." ScienceDaily. ScienceDaily, 2 October 2006. <www.sciencedaily.com/releases/2006/09/060930094117.htm>.
National Institute of Standards and Technology. (2006, October 2). Einstein's Magnetic Effect Is Measured On Microscale. ScienceDaily. Retrieved October 25, 2014 from www.sciencedaily.com/releases/2006/09/060930094117.htm
National Institute of Standards and Technology. "Einstein's Magnetic Effect Is Measured On Microscale." ScienceDaily. www.sciencedaily.com/releases/2006/09/060930094117.htm (accessed October 25, 2014).

Share This



More Matter & Energy News

Saturday, October 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

IKEA Desk Converts From Standing to Sitting With One Button

IKEA Desk Converts From Standing to Sitting With One Button

Buzz60 (Oct. 24, 2014) IKEA is out with a new convertible desk that can convert from a sitting desk to a standing one with just the push of a button. Jen Markham explains. Video provided by Buzz60
Powered by NewsLook.com
Ebola Protective Suits Being Made in China

Ebola Protective Suits Being Made in China

AFP (Oct. 24, 2014) A factory in China is busy making Ebola protective suits for healthcare workers and others fighting the spread of the virus. Duration: 00:38 Video provided by AFP
Powered by NewsLook.com
Real-Life Transformer Robot Walks, Then Folds Into a Car

Real-Life Transformer Robot Walks, Then Folds Into a Car

Buzz60 (Oct. 24, 2014) Brave Robotics and Asratec teamed with original Transformers toy company Tomy to create a functional 5-foot-tall humanoid robot that can march and fold itself into a 3-foot-long sports car. Jen Markham has the story. Video provided by Buzz60
Powered by NewsLook.com
Police Testing New Gunfire Tracking Technology

Police Testing New Gunfire Tracking Technology

AP (Oct. 24, 2014) A California-based startup has designed new law enforcement technology that aims to automatically alert dispatch when an officer's gun is unholstered and fired. Two law enforcement agencies are currently testing the technology. (Oct. 24) Video provided by AP
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