Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Physicists create first metamaterial with rewritable magnetic ordering

23.05.2016

University of Notre Dame physicists and their collaborators have produced the first rewriteable artificial magnetic charge ice. The research, described in a paper published in Science today, shows strong potential for technological applications from information encoding, reprogrammable magnonics, and also to spintronics.

Notre Dame physicist Yong-Lei Wang and his colleagues have found a new way of designing artificial spin ices with controllable magnetic ordered states. The new magnetic metamaterial forms eight types of 'magnetic charge' ordering and enables the first rewritable artificial magnetic charge ice (MCI) which follows the "two-positive two-negative" charge ice rule. The study demonstrates techniques to switch the charge ordering both globally and locally. The 'read-write-erase' multiple recording functionalities are conveniently realized at room temperature.


These are magnetic force microscopy images of the patterned magnetic charge ice with 'ND' letters (initials of Notre Dame).

Credit: Yong-Lei Wang/Zhili Xiao

Artificial spin ice is a class of lithographically created arrays of interacting magnetic nano-islands. Due to its geometrical anisotropy, the elongated nano-scale island forms a single magnetic domain which behaves like 'macro spin' with a binary degree of freedom. The 'spins' in artificial spin ice follows the 'two-in two-out' ice rule that determines the proton positional ordering in water ice.

Scientists have created artificial spin ice systems as models to investigate complex magnetism in crystals and the related physics in a material that can be tailored with specialized properties and be investigated through direct imaging.

Due to the plethora of spin configurations, artificial spin ices have great potential for applications in data storage, memory, and logic devices. However, because of the large magnetic energy scales of these nanoscale islands at room temperature, achieving the magnetic ground and higher ordered states in traditional artificial spin ices have been a big challenge for nearly a decade since the first artificial spin ice was created. This essentially limits the practical application of artificial ices.

"We solved the challenge with a new way of thinking. Instead of focusing on spins, we tackled the associated magnetic charges that allow us to design and create artificial magnetic charge ices with more control," said Wang, who designed the new magnetic nano-structures and built a custom magnetic force microscope (MFM) for the research. He is the first author and co-corresponding author on the study.

The stray magnetic field distribution of each elongated magnetic island can be represented as a dumbbell of magnetic charges, one positive and one negative. Wang and his colleagues demonstrated a very simple way to redesign the spin texture of artificial spin ice while maintaining its magnetic charge map. The decoupling of magnetic spins and magnetic charges enables them to create desired and new magnetic charge ordered states by tuning the magnetic textures through an applied external magnetic field.

"Our realization of tunable artificial magnetic charge ices is similar to the creation of a 'smart' material. It provides a versatile platform to advance our knowledge about artificial spin ices, to discover new physical phenomena and to achieve desired functionalities for applications," said Zhili Xiao, who is the co-corresponding author on the study and holds a joint appointment between Argonne National Laboratory and Northern Illinois University.

The researchers also show how to use a magnetic tip of an MFM as a local perturbation of the applied field to flip 'single spin' and to manipulate local charge ordering. They demonstrated the 'read-write-erase' recording functionality of the magnetic charge ice at room temperature. They created micrometer scale magnetic charge letters 'ND' (the initial letters of Notre Dame) which is an excited magnetic state surrounded by a ground state background. This could lead to a new magnetic micro patterning technique by transferring these magnetic patterns to other materials through magnetolithography.

"By combining these magnetic nano-patterned structures with other materials such as superconductors, our rewritable magnetic charge ice provides an ideal and versatile playground to explore and control new emergent properties that can arise from novel hybrid structures," said Wai-Kwong Kwok, who is the group leader of Argonne's superconducting and magnetism group and is a co-author of this study.

Yong-Lei Wang | EurekAlert!

More articles from Physics and Astronomy:

nachricht A 100-year-old physics problem has been solved at EPFL
23.06.2017 | Ecole Polytechnique Fédérale de Lausanne

nachricht Quantum thermometer or optical refrigerator?
23.06.2017 | National Institute of Standards and Technology (NIST)

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: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>