Abelian Bridge to Non-Abelian Anyons in Ultra-Cold Atoms and Graphene
Abstract
This proposal aims to demonstrate and comprehensively explore nonabelian anyons via an interdependent investigation of solid-state materials and ultracold atoms. Success would constitute a landmark basic-science achievement and mark a critical step towards new quantum technologies, as nonabelian anyons form the basis of fault-tolerant quantum computing architectures. Nonabelian excitations arise in two distinct contexts. First, they can appear ÔintrinsicallyÕ as quasiparticles in strongly correlated topological phases of matter, notably fractional quantum Hall states and quantum spin liquids. Second, nonabelian statistics can appear ÔextrinsicallyÕ from defects engineered in comparatively simple 2D abelian topological phases. In either case, a successful approach must feature widely tunable microscopic interactions, enabling global control over the phase diagram and local control over quasiparticles and defects. Recent advances pioneered by our team in the control of ultra-cold atoms and van der Waals heterostructures provide a timely opportunity to engineer both abelian and nonabelian anyons in conceptually novel and experimentally accessible configurations. Our proposed efforts utilize the shared virtues of cold atoms and van der Waals heterostructuresÑwidely tunable interactions and physical geometriesÑwhile leveraging the special advantages of each platform, namely grapheneÕs unique electronic structure and the ability to tune microscopic cold-atom Hamiltonians with time-dependent potentials. We will develop three experimental avenues to nonabelian physics, focusing on the most promising cold-atom and solid-state candidates: realizing intrinsic nonabelian ground states, engineering synthetic nonabelian defects via Cooper pairing, and creating related defects by purely geometric means. Our general approach is to develop ground states proximal to nonabelian states, and then induce nonabelian behavior using tunable coupling between systems, introduction of defects, or periodic modulation. An important feature of the proposed work is the mutually complementary nature of our solidstate and cold-atom approaches. As an example, cold atoms straightforwardly realize disorder-free systems but often suffer from relatively high temperatures, while solid-state systems can be easily cooled but preclude total control over sample disorder. Even as we advance both fields through innovations in atomic cooling and fabrication of ultra-clean heterostructures, our joint effort will provide ample opportunity for reciprocal quantum emulation: atomic systems can simulate anyonic signatures in disordered solid-state systems using tunable disorder, while finite-temperature effects can be controllably simulated in solid-state systems. In many cases, our proposed platforms admit new probes that have never been applied to anyonic systems, including spatially resolved transport, thermodynamics, and spectroscopic measurementsÑfacilitating an unprecedented characterization of nonabelian anyons not possible in either setting by itself. PUBLICLY RELEASABLE
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Sep 11, 2018
- Source ID
- W911NF1710323
Entities
People
- Andrea Young
Organizations
- Army Contracting Command
- United States Army
- University of California, Santa Barbara