Roman Lutchyn, University of California, Berkeley
Abstract
The exploration of topological phases of matter is one of the main challenges in condensed matter physics. Among the exciting recent developments in this direction are discoveries of the new phases of matter with many intriguing properties, such as topological insulators and superconductors. In this colloquium, I will focus on topological superconductors and discuss how one can engineer non-trivial superconductivity in the laboratory at the interface of a conventional superconductor and a semiconductor with a spin-orbit interaction. I will show that such a topological state emerging at the interface supports zero-energy modes that can be occupied by Majorana quasi-particles. These quasi-particles are exotic in the sense that they are at the same time their own antiparticles. Effectively, they are fractionalized objects (anyons) that obey unconventional exchange statistics. If found, Majorana quasi-particles would constitute a key building block for the implementation of fault-tolerant topological quantum computation schemes that are inherently decoherence-free. I will conclude my talk by reviewing recent experimental efforts in realizing and detecting Majorana zero-energy modes in one-dimensional nanowires.