Скачать или смотреть Discovery of a Quantum Bidimensional Material: Crystal Topological Insulation

Discovery of a Quantum Bidimensional Material: Crystal Topological Insulation

An international team of researchers has achieved a milestone that seemed unattainable: manufacturing a two-dimensional quantum material whose existence had been foreseen only in theory.This material is a crystalline topological insulator in the form of a thin atomic layer, built from tin telide (SnTe) and capable of driving electricity exclusively by its edges.If you like this type of content, do not forget to subscribe to the channel and give like to the video.The particularity of these materials lies in the fact that their interior remains insulating while their edges behave like conductive cables.This property has a huge potential for future applications in high efficiency electronics and quantum computing.The finding puts an end to more than ten years of frustrated attempts to find a practical way to manufacture these two-dimension systems, known as TCIs (topological crystalline insulators but they appear as crystallization states).The study, published in Nature Communications, has shown that it is possible to stabilize these conditions. The great challenge to perform a two-dimensional CRT has been to find a manufacturing method that maintains the necessary symmetry. In this case, researchers grew a two layer film of SnTe on a substrate of niobium disslenide (NbSe2), using a technique known as epitaxis by molecular beams. Thanks to this process, they managed to get the upper layers of the SnT compressed, generating a biaxial tension that induces topological behavior. Experimental data clearly showed the existence of two peaks in the density of states on the edges of the material, signaling that the topological states were active. One of the keys of the study is the use of mechanical tension to activate the topologic properties of the materials. The SnTE in its natural form is not a two dimension CRT, but when applying compression, the electronic structure of the system is modified, leading to a transition of topological phase induced by tension. To confirm that the material created was actually a CTT, the scientists carried out several experiments. The most direct test was the near-exposure of peaks on the density spectrum of states, located in the margins of the nearby channels.