When Impurities Are Desirable: A New Platform for Topological Superconductivity

Topological superconductivity is one of the emerging fields in physics, important both from a fundamental perspective and for its applications, especially in fault-tolerant quantum computing. One of the intriguing routes toward realizing such phases is the use of suitable impurities in superconductors. These impurities can give rise to a useful state in the superconducting mechanism known as the Yu–Shiba–Rusinov (YSR) state. When a large number of such impurities are arranged in a chain or cluster, they can provide a platform for the emergence of topological superconductivity and Majorana fermions. In this talk, I will first give a brief overview of superconductivity and its properties. I will then explain why impurities can play a decisive role. Next, I will show how these impurities can become a platform for discovering new quantum phases. Finally, I will point to the prospects of this exciting field in the design of quantum systems.