Magnetic materials are the backbone of modern digital information technologies, such as hard-disk storage. A University of Washington-led team has now taken this one step further by encoding information using magnets that are just a few layers of atoms in thickness. This breakthrough may revolutionize both cloud computing technologies and consumer electronics by enabling data storage at a greater density and improved energy efficiency.
In a study published online May 3 in the journal Science, the researchers report that they used stacks of ultrathin materials to exert unprecedented control over the flow of electrons based on the direction of their spins — where the electron “spins” are analogous to tiny, subatomic magnets. The materials that they used include sheets of chromium tri-iodide (CrI3), a material described in 2017 as the first ever 2-D magnetic insulator. Four sheets — each only atoms thick — created the thinnest system yet that can block electrons based on their spins while exerting more than 10 times stronger control than other methods.
“Our work reveals the possibility to push information storage based on magnetic technologies to the atomically thin limit,” said co-lead author Tiancheng Song, a UW doctoral student in physics.
“With the explosive growth of information, the challenge is how to increase the density of data storage while reducing operation energy,” said corresponding author Xiaodong Xu, a UW professor of physics and of materials science and engineering, and faculty researcher at the UW Clean Energy Institute. “The combination of both works points to the possibility of engineering atomically thin magnetic memory devices with energy consumption orders of magnitude smaller than what is currently achievable.”
The new Science paper also looks at how this material could allow for a new type of memory storage that exploits the electron spins in each individual sheet.
The researchers sandwiched two layers of CrI3 between conducting sheets of graphene. They showed that, depending on how the spins are aligned between each of the CrI3 sheets, the electrons can either flow unimpeded between the two graphene sheets or were largely blocked from flowing. These two different configurations could act as the bits — the zeroes and ones of binary code in everyday computing — to encode information.
“The functional units of this type of memory are magnetic tunnel junctions, or MTJ, which are magnetic ‘gates’ that can suppress or let through electrical current depending on how the spins align in the junction,” said co-lead author Xinghan Cai, a UW postdoctoral researcher in physics. “Such a gate is central to realizing this type of small-scale data storage.”
With up to four layers of CrI3, the team discovered the potential for “multi-bit” information storage. In two layers of CrI3, the spins between each layer are either aligned in the same direction or opposite directions, leading to two different rates that the electrons can flow through the magnetic gate. But with three and four layers, there are more combinations for spins between each layer, leading to multiple, distinct rates at which the electrons can flow through the magnetic material from one graphene sheet to the other.
“Instead of your computer having just two choices to store a piece of data in, it can have a choice A, B, C, even D and beyond,” said co-author Bevin Huang, a UW doctoral student in physics. “So not only would storage devices using CrI3 junctions be more efficient, but they would intrinsically store more data.”
The researchers’ materials and approach represent a significant improvement over existing techniques under similar operating conditions using magnesium oxide, which is thicker, less effective at blocking electrons and lacks the option for multi-bit information storage.
“Although our current device requires modest magnetic fields and is only functional at low temperature, infeasible for use in current technologies, the device concept and operational principle are novel and groundbreaking,” said Xu. “We hope that with developed electrical control of magnetism and some ingenuity, these tunnel junctions can operate with reduced or even without the need for a magnetic field at high temperature, which could be a game changer for new memory technology.”
The Latest on: Atomically thin magnetic device
via Google News
The Latest on: Atomically thin magnetic device
- Two-dimensional magnetic crystals and emergent heterostructure devices on February 14, 2019 at 11:40 am
The ability to knit such magnetic order in atomically thin flatlands would foster vast opportunities for integrated, flexible, and biocompatible devices; however, such two-dimensional (2D) magnets are ... […]
- Atomically thin magnetic device may revolutionize memory storage technologies: study on May 3, 2018 at 8:29 pm
A team led by University of Washington researchers reported on Thursday in the journal Science a new way to encode information using magnets that are just a few layers of atoms in thickness. The findi... […]
- Atomically thin magnetic device may revolutionize memory storage technologies: study on May 3, 2018 at 3:17 pm
WASHINGTON, May 3 (Xinhua) -- A team led by University of Washington researchers reported on Thursday in the journal Science a new way to encode information using magnets that are just a few layers of ... […]
- Atomically thin magnetic device could lead to new memory technologies on May 3, 2018 at 11:06 am
Magnetic materials are the backbone of modern digital information technologies, such as hard-disk storage. A University of Washington-led team has now taken this one step further by encoding informati... […]
- Atomically thin magnetic device could lead to new memory technologies on May 3, 2018 at 11:05 am
In the experiment, the researchers sandwiched two atomic layers of CrI3 between graphene contacts and measured the electron flow through the CrI3. Credit: Tiancheng Song Magnetic materials are the bac... […]
- Atomically thin magnetic device could lead to new memory technologies on May 2, 2018 at 5:00 pm
The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering. In fiscal year (FY) 2018, its budg... […]
- Breakthrough made in atomically thin magnets on April 3, 2018 at 7:03 am
Shan and Mak, who specialize in researching atomically thin materials, jumped on the opportunity ... “the majority of existing technology is based on magnetic switching, like in memory devices that re... […]
- Scientists identify hundreds of atomically thin materials on February 11, 2018 at 7:07 am
These have a variety of properties—some are semiconductors and have been combined with graphene to make electronic devices. To expand the range of devices we can craft that build on the advantages of ... […]
- Berkeley Lab Scientists Discover New Atomically Layered, Thin Magnet on April 26, 2017 at 10:24 am
The scientists found that a 2-D van der Waals crystal, part of a class of material whose atomically thin layers can be peeled off one ... such as nanoscale memory, spintronic devices, and magnetic sen... […]
via Bing News