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 New NASA study improves search for habitable worlds
20.10.2017 | NASA/Goddard Space Flight Center

nachricht Physics boosts artificial intelligence methods
19.10.2017 | California Institute of Technology

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: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>