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Taylor, J M

Publications and source records attributed to Taylor, J M.

Unified approach to topological quantum computation with anyons: From qubit encoding to Toffoli gate

Topological quantum computation may provide a robust approach for encoding and manipulating information utilizing the topological properties of anyonic quasiparticle excitations. We develop an efficient means to map between dense and sparse representations of quantum information (qubits) and a simple construction of multiqubit gates, for all anyon models from Chern-Simons-Witten SU(2){sub k} theory that support universal quantum computation by braiding (k{>=}3, k{ne}4). In the process, we show how the constructions of topological quantum memory and gates for k=2,4 connect naturally to those for k{>=}3, k{ne}4, unifying these concepts in a simple framework. Furthermore, we illustrate potential extensions of these ideas to other anyon models outside of Chern-Simons-Witten field theory.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Fast and robust quantum computation with ionic Wigner crystals

We present a detailed analysis of the modulated-carrier quantum phase gate implemented with Wigner crystals of ions confined in Penning traps. We elaborate on a recent scheme, proposed by two of the authors, to engineer two-body interactions between ions in such crystals. We analyze the situation in which the cyclotron ({omega}{sub c}) and the crystal rotation ({omega}{sub r}) frequencies do not fulfill the condition {omega}{sub c}=2{omega}{sub r}. It is shown that even in the presence of the magnetic field in the rotating frame the many-body (classical) Hamiltonian describing small oscillations from the ion equilibrium positions can be recast in canonical form. As a consequence, we are able to demonstrate that fast and robust two-qubit gates are achievable within the current experimental limitations. Moreover, we describe a realization of the state-dependent sign-changing dipole forces needed to realize the investigated quantum computing scheme.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗