Electric Skyrmions Charge Ahead for Next-Generation Data Storage
April 19, 2019 | Berkeley LabEstimated reading time: 6 minutes
To confirm their observations, senior staff scientist Elke Arenholz and staff scientist Padraic Shafer at Berkeley Lab’s Advanced Light Source (ALS), along with Margaret McCarter, a physics Ph.D. student from the Ramesh Lab at UC Berkeley, probed the chirality by using a spectroscopic technique known as RSXD-CD (resonant soft X-ray diffraction circular dichroism), one of the highly optimized tools available to the scientific community at the ALS, a U.S. DOE Office of Science User Facility that specializes in lower energy, “soft” X-ray light for studying the properties of materials.
Simulations of skyrmion bubbles and elongated skyrmions for the lead titanate/strontium titanate superlattice. (Credit: Berkeley Lab)
Light waves can be “circularly polarized” to also have handedness, so the researchers theorized that if polar skyrmions have handedness, a left-handed skyrmion, for example, should interact more strongly with left-handed, circularly polarized light – an effect known as circular dichroism.
When McCarter and Shafer tested the samples at the ALS, they successfully uncovered another piece to the chiral skyrmion puzzle – they found that incoming circularly polarized X-rays, like a screw whose threads rotate either clockwise or counterclockwise, interact with skyrmions whose dipoles rotate in the same direction, even at room temperature. In other words, they found evidence of circular dichroism – where there is only a strong interaction between X-rays and polar skyrmions with the same handedness.
“The theoretical simulations and microscopy both revealed the presence of a Bloch component, but to confirm the chiral nature of these skyrmions, the last piece of the puzzle was really the circular dichroism measurements,” McCarter said. “It is amazing to observe this effect in materials that typically don’t have handedness. We are excited to explore the implications of this chirality in a ferroelectric and how it can be controlled in a way that could be useful for storing data.”
Now that the researchers have made a single electric skyrmion and confirmed its chirality, they plan to make an array of dozens of electric skyrmions – each one with a diameter of just 8 nm (for comparison, the Ebola virus is about 50 nm wide) – with the same handedness. “In terms of applications, this is exciting because now we have chirality – switching a skyrmion on or off, or between left-handed and right-handed – on top of still being able to use the charge for storing data,” Ramesh said.
The researchers next plan to study the effects of applying an electric field on the polar skyrmions. “Now that we know that polar/electric skyrmions are chiral, we want to see if we can electrically manipulate them. If I apply an electric field, can I turn each one like a turnstile? Can I move each one, one at a time, like a checker on a checkerboard? If we can somehow move them, write them, and erase them for data storage, then that would be an amazing new technology,” Ramesh said.
Also contributing to the study were researchers from Pennsylvania State University, Cornell University, and Oak Ridge National Laboratory.
The work was supported by the DOE Office of Science with additional funding provided by the Gordon and Betty Moore Foundation’s EPiQS Initiative, the National Science Foundation, the Luxembourg National Research Fund, and the Spanish Ministry of Economy and Competitiveness.
VIDEO: Simulation of a single polar skyrmion. Red arrows signify that this is a left-handed skyrmion. The other arrows represent the angular distribution of the dipoles. (Credit: Xiaoxing Cheng, Pennsylvania State University; C.T. Nelson, Oak Ridge National Laboratory; and Ramamoorthy Ramesh, Berkeley Lab)
Page 2 of 2Suggested Items
Koh Young Extends Invitation to the 2024 IEEE Electronic Components and Technology Conference
04/30/2024 | Koh YoungKoh Young, the industry leader in True3D measurement-based inspection solutions, invites you to join us at the at the 2024 IEEE Electronic Components and Technology Conference from May 28-31, 2024, in Denver, Colorado at the Gaylord Rockies Resort & Convention Center.
Real Time with... IPC APEX EXPO 2024: Sustainability in the Industry
04/26/2024 | Real Time with...IPC APEX EXPOGuest Editor Henry Crandall and Chris Nash of Indium Corporation discuss the company's 90th anniversary and its focus on sustainability. They focus on the benefits of sustainable materials, their compatibility, and value propositions. The conversation also highlights how Durafuse LT technology's role in reducing reflow temperatures is leading to significant cost and energy savings. Nash also touches on downstream sustainability efforts such as using recycled materials for packaging.
I-Connect007 Editor’s Choice: Five Must-Reads for the Week
04/26/2024 | Andy Shaughnessy, Design007 MagazineIn this week’s roundup, we have a variety of articles covering everything from design through assembly, and even box build. I’ve always wondered whether box build was all it was cracked up to be. Do customers really pick one EMS provider over another because one company offers box build? And if you’ve ever wanted to volunteer, IPC’s Thought Leaders Program is looking for a few good technologists to help them on their mission. Check out Stanton Rak’s article, which was published in the spring issue of IPC Community.
Taiyo Circuit Automation Installs New DP3500 into Fuba Printed Circuits, Tunisia
04/25/2024 | Taiyo Circuit AutomationTaiyo Circuit Automation is proud to be partnered with Fuba Printed Circuits, Tunisia part of the OneTech Group of companies, a leading printed circuit board manufacturer based out of Bizerte, Tunisia, on their first installation of Taiyo Circuit Automation DP3500 coater.
LPKF Extends Contract of CEO Klaus Fiedler until 2028
04/24/2024 | LPKFThe Supervisory Board of LPKF Laser & Electronics SE has decided to extend the contract of Dr. Klaus Fiedler as CEO until 31 December 2028. "Under the leadership of Klaus Fiedler, LPKF has undergone some extensive transformation since he joined just over 2 years ago.