Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Engineered materials: Custom-made magnets

24.05.2012
A novel approach to designing artificial materials could enable magnetic devices with a wider range of properties than those now available. An international team of researchers have now extended the properties and potential uses of metamaterials by using not one but two very different classes of nanostructures, or metamolecules.

The properties of a substance are largely dependent on its constituent atoms and the way that these atoms interact with each other. The finite number of atom types, however, imposes a limit on the range of properties that a conventional material can have.


An array of metamolecules comprising silicon spheres and copper split-rings can be used to control magnetization waves.
Copyright : © 2012 American Chemical Society

In contrast, a new class of engineered materials called metamaterials have no such limitation. Metamaterials are typically composed of an array of nanostructures that can interact with electromagnetic waves in much the same way as atoms. In addition, the optical properties of these metamaterials can be tuned by altering the size and shape of nanostructures.

An international team of researchers led by Boris Luk'yanchuk at the A*STAR Data Storage Institute have now extended the properties and potential uses of metamaterials by using not one but two very different classes of nanostructures, or metamolecules.

Luk'yanchuk and the team mathematically modelled a two-dimensional array of metamolecules comprising a silicon sphere next to a partially incomplete copper ring. They studied the influence of both the sphere and the split ring on the magnetic component of an incident electromagnetic wave — a property known as magnetization.

"When the two structures were more than one micrometer apart, they both acted to increase the local magnetic field," says Luk’yanchuk. However, they started to interact when moved closer together, and the researchers observed that the magnetization of the split ring decreases and even becomes negative for separations smaller than 0.5 micrometers.

This situation is somewhat analogous to the magnetic ordering in ‘natural’ materials. When all the atoms contribute in a positive way to a material’s magnetic properties, the material becomes a ferromagnet. However, when alternating regions of the material have opposite magnetization, the material is said to be antiferromagnetic.

"We demonstrate that our hybrid lattices of metamolecule exhibit distance-dependent magnetic interaction, opening new ways for manipulating artificial antiferromagnetism with low-loss materials," explains Luk'yanchuk.

Although the analogy between metamaterials and magnetic materials is not a perfect one, most metamaterials are said to be ferromagnet-like. The design proposed by Luk'yanchuk and the team closely mimics antiferromagnetic ordering, and this opens an opportunity for researchers to study antiferromagnetic phenomena in metamaterials. One notable example is giant magnetoresistance, a phenomenon that is at the heart of modern electronic memories.

Luk'yanchuk affirms that a metamaterial analog would offer exciting research prospects. "We believe that our work has the potential to make a strong impact towards the development of on-chip integrated solutions for reconfigurable and optically-controlled metamaterials."

The A*STAR-affiliated researchers contributing to this research are from the Data Storage Institute.

References:

Miroshnichenko, A. E., Luk'yanchuk, B., Maier, S. A. & Kivshar, Y. S. Optically induced interaction of magnetic moments in hybrid metamaterials. ACS Nano 6, 837–842 (2012).

Lee Swee Heng | Research asia research news
Further information:
http://www.a-star.edu.sg
http://www.researchsea.com

More articles from Materials Sciences:

nachricht Scientists predict a new superhard material with unique properties
18.06.2018 | Moscow Institute of Physics and Technology

nachricht A sprinkle of platinum nanoparticles onto graphene makes brain probes more sensitive
15.06.2018 | University of California - San Diego

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

Im Focus: Photoexcited graphene puzzle solved

A boost for graphene-based light detectors

Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...

Im Focus: Water is not the same as water

Water molecules exist in two different forms with almost identical physical properties. For the first time, researchers have succeeded in separating the two forms to show that they can exhibit different chemical reactivities. These results were reported by researchers from the University of Basel and their colleagues in Hamburg in the scientific journal Nature Communications.

From a chemical perspective, water is a molecule in which a single oxygen atom is linked to two hydrogen atoms. It is less well known that water exists in two...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Novel method for investigating pore geometry in rocks

18.06.2018 | Earth Sciences

Diamond watch components

18.06.2018 | Process Engineering

New type of photosynthesis discovered

18.06.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>