The world's first 2D magnet with a thickness of one atom is stable even at 100 degrees Celsius Physics

The world's first 2D magnet with a thickness of one atom is stable even at 100 degrees Celsius

The search for two—dimensional materials with magnetic properties is one of the promising areas of modern science. In 2017, scientists have already published a study of a ferromagnetic material called chromium triiodide, which, as it turned out, can be crushed to a monolayer with a thickness of one atom, while maintaining magnetism.

Scientists from the Lawrence Berkeley National Laboratory and the University of California at Berkeley are working to eliminate one of the disadvantages of such 2D magnets, namely instability at room temperature, due to which they lose their magnetic properties. Until now, this has limited the practicality of the technology, but now researchers have found a promising way to solve the problem.

Modern two—dimensional magnets need very low temperatures," explains senior author Jie Yao. — But for practical reasons, the data center should work at room temperature. Our 2D magnet is not only the first magnet operating under such conditions, but also the first magnet to achieve true two-dimensionality: its thickness is only one atom!

The scientists started with a mixture of graphene oxide, zinc and cobalt, which was baked in the laboratory and transformed into a layer of zinc oxide, over which cobalt atoms were randomly scattered. The thickness of this layer was only one atom. This layer was sandwiched between two layers of graphene, which completely burned in the process, leaving behind a 2D magnetic film.

In subsequent experiments, the team found that magnetism could be controlled by changing the amount of cobalt in the material. A concentration of 5-6% percent of cobalt atoms resulted in a relatively weak magnet, and an increase in concentration to 12% percent created a very strong magnet. An increase in the amount of cobalt to 15% has led to what scientists call the quantum state of frustration, when conflicting magnetic states in a material compete with each other.

It is important to note that the team found that, unlike previous versions of 2D magnets, the new material retained its magnetic properties at temperatures up to 100 °C - a completely unprecedented case.

A two-dimensional magnet is a million times thinner than a sheet of paper, and therefore can be bent into almost any shape. One of the promising applications of this technology is data storage. The memory devices used today are based on very thin magnetic films that remain three-dimensional and are hundreds or thousands of atoms thick. Thinner magnets, especially magnets with a thickness of just one atom, will allow data to be stored with a much higher density.

This material also opens up new possibilities for studying the world of quantum physics, allowing you to observe individual magnetic atoms and the interactions between them. Another possibility concerns the field of spintronics, where the spin of electrons, and not their charge, will be used for storing and processing data. Scientists suggest that a 2D magnet can become part of a compact device that facilitates these processes.