Breakthrough Made in Atomically Thin Magnets
April 6, 2018 | Cornell UniversityEstimated reading time: 2 minutes
Cornell researchers have become the first to control atomically thin magnets with an electric field, a breakthrough that provides a blueprint for producing exceptionally powerful and efficient data storage in computer chips, among other applications.
The research is detailed in the paper, “Electric-field switching of two-dimensional van der Waals magnets,” published March 12 in Nature Materials by Jie Shan, professor of applied and engineering physics; Kin Fai Mak, assistant professor of physics; and postdoctoral scholar Shengwei Jiang.
In 1966, Cornell physicist David Mermin and his postdoc Herbert Wagner theorized that 2-D magnets could not exist if the spins of their electrons could point in any direction. It wasn’t until 2017 that some of the first 2-D materials with the proper alignment of spins were discovered, opening the door to an entirely new family of materials known as 2-D van der Waals magnets.
Shan and Mak, who specialize in researching atomically thin materials, jumped on the opportunity to research the new magnets and their unique characteristics.
“If it’s a bulk material, you can’t easily access the atoms inside,” said Mak. “But if the magnet is just a monolayer, you can do a lot to it. You can apply an electric field to it, put extra electrons into it, and that can modulate the material properties.”
Using a sample of chromium triiodide, the research team set out to do just that. Their goal was to apply a small amount of voltage to create an electric field and control the 2-D compound’s magnetism, giving them the ability to switch it on and off.
To achieve this, they stacked two atomic layers of chromium triiodide with atomically thin gate dielectrics and electrodes. This created a field-effect device that could flip the electron-spin direction in the chromium triiodide layers using small gate voltages, activating the magnetic switching. The process is reversible and repeatable at temperatures under 57-degrees Kelvin.
The discovery is an important one for the future of electronics because “the majority of existing technology is based on magnetic switching, like in memory devices that record and store data,” said Shan. However, magnets in most modern electronics don’t respond to an electric field. Instead, a current is passed through a coil, creating a magnetic field that can be used to switch the magnet on and off. It’s an inefficient method because the current creates heat and consumes electrical power.
Two-dimensional chromium-triiodide magnets have a unique advantage in that an electric field can be directly applied to activate the switching, and very little energy is required.
“The process is also very effective because if you have a nanometer thickness and you apply just one volt, the field is already 1 volt per nanometer. That’s huge,” said Shan.
The research team plans to continue exploring 2-D magnets and hopes to form new collaborations around campus, including with scientists and engineers who can help them find new 2-D magnetic materials that, unlike chromium triiodide, can work at room temperature.
“In a sense, what we have demonstrated here is more like a device concept,” said Mak. “When we find the right kind of material that can operate at a higher temperature, we can immediately apply this idea to those materials. But it’s not there yet.”
Suggested Items
Untapped Potential: Automating Warehouse Management Into the Present
10/15/2024 | Josh Casper, Horizon SalesThe push toward automation in electronics manufacturing has led to significant improvements in SMT and through-hole technology (THT) production. Today’s manufacturers are outfitted with precision pick-and-place machines, sophisticated inspection systems, and advanced solder deposition solutions. These investments reflect a broader industry trend toward automating high-value production tasks to boost efficiency, improve quality, and reduce headcount in a shrinking labor market. While the spotlight has rightly focused on automating SMT production, one crucial area remains woefully under-invested: materials storage and handling.
Ventec Promotes Bill Wang to Group Technical Vice President
10/14/2024 | VentecVentec International Group, a Taiwan Stock Exchange listed global supplier of advanced base materials for the PCB industry worldwide, has promoted Bill Wang to Group Technical Vice President.
Molg Raises $5.5M in Seed Funding to Tackle Electronics Waste Through Circular Manufacturing
10/11/2024 | PRNewswireMolg Inc. announces the closing of $5.5 million in seed funding to scale the company's circular manufacturing processes for electronics and electrical components. Closed Loop Partners' Ventures Group led the round, with participation from Amazon Climate Pledge Fund,
It’s a Wrap for PCB West 2024
10/11/2024 | Marcy LaRont, PCB007 MagazinePCB West 2024 wraps up Friday, Oct. 11 at the Santa Clara Convention Center (SCCC) in sunny Santa Clara, California. The SCCC is situated next to the “new” Levi’s Stadium, home to the San Francisco 49ers, and directly adjacent to California’s Great America amusement park—both noteworthy landmarks for natives like me. The technical conference, Oct. 8-11, featured 50 technical presentations by 39 different speakers.
Ventec Consolidates and Upgrades European Production and Logistics Center in Germany
10/10/2024 | VentecVentec International Group has begun consolidating operations and installing new, state-of-the-art facilities at its European production and logistics hub in Kirchheimbolanden, Germany.