According to the editors of the journal Nature, a group of scientists from the University of Washington managed to get a connection on the basis of chromium and iodine. The structure of the compound is something of a counterpart of graphene, with a thickness of only 1 atom. This new compound has pronounced magnetic properties, representing, in fact, “two-dimensional planar magnet.”
All the magnetic materials consist of special areas called “domains”. As a rule, the spins of the electrons of the atoms in the domains are rotated in the direction opposite to that in which the parties directed electron spins in neighboring domains. Thanks to this, some metals not having magnetic field can be magnetized under the influence of an external magnetic field. This ability of materials to change properties under the influence of a magnetic field is used in the development of new magnetic storage of information. Scientists believe that by using magnetic materials having a flat structure, it is possible to achieve significant progress in the development of new media based on magnets. During the series of tests, the scientists were able to create several versions of two-dimensional magnets, using technology that was used by the creators of graphene to obtain the first samples of this material. As said one of the participants of the project Xu Xiaodong,
“Long known that salt triode chromium (CrI3), the connection of the three iodine atoms and one atom of chromium has magnetic properties that can in theory be stored in a flat layer of salt. The problem was that previously, it was impossible to synthesize a single layer of molecules of this compound. Moreover, many physicists doubted that a CrI3, or any other magnetic material will retain its properties when turning in a two-dimensional structure.”
A team of scientists has solved this problem in an elegant manner: “tearing off” a few strands of triiodide chromium from the three-dimensional connection, the experts measured their magnetic properties and a number of other characteristics. Similarly, scientists have created a 2D magnet using an alloy of chromium, germanium and tellurium. Interesting that triode chrome loses its properties if to tear from two layers of molecules, but retains them in the presence of three or more layers. Why is this happening, scientists still don’t know.
“Two-dimensional magnets are extremely interesting in themselves, since they can very clearly and precisely change the magnetic properties of their individual parts. But even more interesting is the combination of several heterogeneous layers of this kind. In this case, inside they can encounter exotic phenomena that we’ve never seen before”.
Based on materials of agencies of RIA “news”
Created the first two-dimensional magnet with a thickness of one atom
Vladimir Kuznetsov