Researchers from Tel Aviv University have engineered the world’s tiniest technology, with a thickness of only two atoms.
The new technology, enabling the storage of information in the thinnest unit known to science, is expected to improve future electronic devices in terms of density, speed, and efficiency.
According to the researchers, the new technology proposes a way for storing electric information in the thinnest unit known to science, in one of the most stable and inert materials in nature. The allowed quantum-mechanical electron tunneling through the atomically thin film may boost the information reading process far beyond current technologies.
The research group includes Maayan Vizner Stern, Yuval Waschitz, Dr. Wei Cao, Dr. Iftach Nevo, Prof. Eran Sela, Prof. Michael Urbakh, Prof. Oded Hod, and Dr. Moshe Ben Shalom. The work is now published in Science magazine.
“Our research stems from curiosity about the behavior of atoms and electrons in solid materials, which has generated many of the technologies supporting our modern way of life,” says Dr. Ben Shalom.
“We try to understand, predict, and even control the fascinating properties of these particles as they condense into an ordered structure that we call a crystal. At the heart of the computer, for example, lies a tiny crystalline device designed to switch between two states indicating different responses – “yes” or “no”, “up” or “down” etc. Without this dichotomy – it is not possible to encode and process information. The practical challenge is to find a mechanism that would enable switching in a small, fast, and inexpensive device,” he explained.
Current state-of-the-art devices consist of tiny crystals that contain only about a million atoms, about a hundred atoms in height, width, and thickness, so that a million of these devices can be squeezed about a million times into the area of one coin, with each device switching at a speed of about a million times per second.
Following the technological breakthrough, the researchers were able, for the first time, to reduce the thickness of the crystalline devices to two atoms only.
Dr. Ben Shalom emphasizes that such a thin structure enables memories based on the quantum ability of electrons to hop quickly and efficiently through barriers that are just several atoms thick. Thus, it may significantly improve electronic devices in terms of speed, density, and energy consumption.
In the study, the researchers used a two-dimensional material: one-atom-thick layers of boron and nitrogen, arranged in a repetitive hexagonal structure. In their experiment, they were able to break the symmetry of this crystal by artificially assembling two such layers.
“In its natural three-dimensional state, this material is made up of a large number of layers placed on top of each other, with each layer rotated 180 degrees relative to its neighbors (antiparallel configuration)” says Dr. Ben Shalom. “In the lab, we were able to artificially stack the layers in a parallel configuration with no rotation, which hypothetically places atoms of the same kind in perfect overlap despite the strong repulsive force between them (resulting from their identical charges). In actual fact, however, the crystal prefers to slide one layer slightly in relation to the other, so that only half of each layer’s atoms are in perfect overlap, and those that do overlap are of opposite charges – while all others are located above or below an empty space – the center of the hexagon. In this artificial stacking configuration, the layers are quite distinct from one another. For example, if in the top layer only the boron atoms overlap, in the bottom layer it’s the other way around.”
Dr. Ben Shalom also highlighted the work of the theory team, which conducted numerous computer simulations. “Together we established deep understanding of why the system’s electrons arrange themselves just as we had measured in the lab. Thanks to this fundamental understanding, we expect fascinating responses in other symmetry-broken layered systems as well,” he said.