Recently, the doctoral student Qin Wei of the National Laboratory of the Hefei National Laboratory for Physical Sciences at the China National University of Science and Technology has made new progress in the theoretical study of quantum materials and proposed new methods for the realization of chiral topological superconductors and Mayorana Fermions. Feasible system. Relevant research results were published in the "Physical Review Letters" on December 31, 2014. Topological superconductors and Mayorana Fermi are the focus of attention in the field of condensed matter physics. Mayorana Fermions are their own antiparticles, obey non-Abelian quantum statistics, and can therefore be used to implement topological quantum computations. Theoretically, Mayorana fermions can exist in topological superconductors. For example, quantum flux vortices without spin-p-wave superconductors and semi-quantum magnetic flux vortices with spin-p-wave superconductors all have zero energy around them. Mayorana Fermi. Experimentally, it is controversially observed that the presence of Maiorana Fermi is a huge challenge facing the physical world. A few years ago, C. Kane, a graduate of the Junior College of Science and Engineering, currently teaching at MIT, and his mentor, the American scientist C. Kane, predicted for the first time that it can be achieved through the proximity effect between s-wave superconductors and three-dimensional topological insulators. Effective p-wave superconductors. In order to further realize the chiral topological superconductors, the time reversal symmetry must be broken. Based on the work of Fu Liang and Kane, people designed a sandwich heterojunction consisting of a ferromagnetic insulator, a strong spin-orbit coupled semiconductor film, and an s-wave superconductor. The Zeeman field failure time inversion introduced by the proximity effect Symmetry, so that chiral topological superconductors can be realized. These theoretical predictions led to the experimental observation of Mayorana Fermat's research boom in the field of condensed matter physics. However, due to the complexity of the system, previous reports are controversial. How to realize chiral topological superconductors in a simpler structure and further observe Mayorana Fermions has a wide range of basic research and application values. In his newly published work, Qin Wei first proposed to break the time inversion symmetry by diluting doped magnetic atoms at the interface between the topological insulator and the s-wave superconductor (as shown in Figure (a)), and thus can Realizes chiral topological superconductors for simple structures. Their research shows that moderate magnetic atoms not only do not destroy the superconductivity of the superconductor and the topological insulator interface (Fig. (b)), but also enable long-range ferromagnetic ordering through Cooper electron pairs belonging to the interface topological states. . Due to the coexistence of superconductivity and ferromagnetism, chiral topological superconductors can be realized by temperature-induced topological quantum phase transition (Fig. (c)), and further provide a new and more feasible platform for experimental detection of Mayolana Fermions. The obvious advantage is that set superconductivity, topology and magnetism are in the same interface. The above research was funded by the National Natural Science Foundation of China, the Ministry of Science and Technology, and the Center for Quantum Information and Quantum Science Collaborative Innovation. Guangzhou Jointair Co., Ltd. , https://www.jointairaccessories.com
China University of Science and Technology has made new progress in the theoretical study of quantum materials