Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Novel material may demonstrate long-sought ’liquid’ magnetic state

09.09.2005


A novel material that may demonstrate a highly unusual "liquid" magnetic state at extremely low temperatures has been discovered by a team of Japanese and U.S. researchers, according to tomorrow’s issue of Science.*


A crystal diagram shows the triangle-shaped atomic structure of nickel gallium sulfide, which may have an unusual "liquid" magnetic state at low temperatures. Red spheres represent nickel, green spheres are gallium, and yellow are sulfur. Image credit: S. Nakatsuji et al., Science, 9/9/2005


Multi-colored arrows show the disordered array of magnetic spins associated with the electrons of nickel within NiGa2S4. The data were collected by precisely measuring the change in speed and direction of neutrons as they were passed through the material and interacted with the electrons. Image credit: S. Nakatsuji et al., Science, 9/9/2005



The material, nickel gallium sulfide (NiGa2S4), was synthesized by scientists at Kyoto University. Its properties were studied by both the Japanese team and by researchers from The Johns Hopkins University (JHU) and the University of Maryland (UM) at the Commerce Department’s National Institute of Standards and Technology (NIST).

The scientists studied the polycrystalline sample using both X-rays and neutrons as probes to understand its structure and properties. The neutron experiments were conducted at the NIST Center for Neutron Research.


The team found that the triangular arrangement of the material’s atoms appears to prevent alignment of magnetic "spins," the characteristic of electrons that produces magnetism. A "liquid" magnetic state occurs when magnetic spins fluctuate in a disorderedly, fluid-like arrangement that does not produce an overall magnetic force. The state was first proposed as theoretically possible about 30 years ago. A liquid magnetic state may be related to the similarly fluid way that electrons flow without resistance in superconducting materials.

According to Collin Broholm, a professor in the Department of Physics and Astronomy at The Johns Hopkins University in Baltimore, "the current work shows that at an instant in time the material looks like a magnetic liquid, but whether there are fluctuations in time, as in a liquid, remains to be seen."

Each electron can be thought of as a tiny bar magnet. The direction of its "north" pole is its spin. "An ordered pattern of spins generally uses less energy," says Broholm, "but the triangular crystal structure prevents this from happening in this material."

The team conducted their neutron experiments with an instrument called a "disk chopper spectrometer." The only one of its kind in North America, the instrument sends bursts of neutrons of the same wavelength through a sample. Then, more than 900 detectors arranged in a large semicircle determine exactly where and when the neutrons emerge, providing information key to mapping electron spins.

"The energy range and resolution we can achieve with this instrument is ideal for studying magnetic systems," adds Yiming Qiu, a NIST guest researcher from UM.

The wavelength of the slowed-down (cold) neutrons available at the NIST facility--less than 1 nanometer (billionth of meter)--also allows the researchers to study nanoscale magnetic properties too small to be measured with other methods.

* S. Nakatsuji, Y. Nambu, H. Tonomura, O. Sakai, S. Jonas, C. Broholm, H. Tsunetsugu, Y. Qiu, Y. Maeno. "Spin Disorder on a triangular lattice." Science, Sept. 9, 2005.

Gail Porter | EurekAlert!
Further information:
http://www.nist.gov

More articles from Materials Sciences:

nachricht Materials scientist creates fabric alternative to batteries for wearable devices
12.11.2018 | University of Massachusetts at Amherst

nachricht A new path through the looking-glass
12.11.2018 | Deutsches Elektronen-Synchrotron DESY

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

Im Focus: Coping with errors in the quantum age

Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly

The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

The dawn of a new era for genebanks - molecular characterisation of an entire genebank collection

13.11.2018 | Life Sciences

Fish recognize their prey by electric colors

13.11.2018 | Life Sciences

Ultrasound Connects

13.11.2018 | Awards Funding

VideoLinks
Science & Research
Overview of more VideoLinks >>>