Detection, Characterization, and Manipulation of Majorana Fermions
Abstract
Objective:Since the initial prediction by Italian physicist Ettore Majorana more than 70 years ago, the search for the odd particle now bears his name -- Majorana fermion (MF), which is also its own anti-particle, has shifted from high energy physics to relatively standard condensed matter systems. Indeed initial experimental results with excitations that are consistent with MF has been observed and reported by several research groups worldwide. If confirmed, MF has far reaching implications in robust quantum information processing and possibly other areas of applications. The objectve of this Basic Research Challenge (BRC) project is to carry out fundamental research to achieve a thorough understanding of the mechanisms, conditions and materials constraints that ultimately leads to unambiguous demonstration of Majorana fermions in solid state systems.Approach:The team has proposed i) a broad experimental and theoretical programbased on a magnetically textured nanostructures on the surface of a superconductor that will provide direct means of detecting and characterizing MFs, and ii) a program to build device-like structures in which these excitations will be easily manipulated. The manipulation experiments will be used to demonstrate topological characteristics and develop protocols that can ultimatelybe used to perform braiding of these excitations.The program is built on the team?s recent theoretical calculations which demonstrate that atomic chains of magnetic atoms on the surface of a superconductor can host MFs localized at the ends of the chains. This approach is an attractive alternative to, and complements, more popular schemes based on semiconductor nanowires or topological insulators, and is being validated by scanning tunneling microscopy (STM) and spectroscopy experiments that show strong evidence for MFs in nanoscale magnetic chains on the surface of a superconductor. The team proposes to significantly expand the initial ideas and experiments that will optimize the MFs in their magnetically textured systems and will also create unique nanostructures and associated devices in which MFs can be easily manipulated. A significant advantage of the current experimental approach for creation and detection of MFs is the use of atomically precisestructures with a known geometry and well characterized electronic and spin structures obtained from in situ STM experiments. This atomic scale information lends itself to precise bottom-up modeling of the electronic properties and will make it possible to optimize their solid-state MF system. The successful outcome of this program will likely be an unequivocal detection of MFs, but also direct manipulation of MFs to demonstrate their topological properties and thereby to experimentally establish the processes on which computations would be based.ONR Mission/Relevance:Scientifically, this project is aimed at developing the basic physics of the Majorana fermion and its dynamics in the context of new topological materials and heterostructures. Practically, the project will lay the foundation for future electronic devices with possible order-of-magnitude reductions in computational energy that enable advanced computing schemes that will contribute directly to the Naval goal of information dominance. There have been no prior efforts in this topic at ONR. As a relatively unexplored area, there is an intrinsic opportunity to attract new performers into the field and to engage with the Navy.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Sep 21, 2018
- Source ID
- N000141612391
Entities
People
- Ali Yazdani
Organizations
- Office of Naval Research
- Trustees of Princeton University
- United States Navy