Search for dissertations about: "Completely Positive Maps"

Found 3 swedish dissertations containing the words Completely Positive Maps.

  2. 1. Geometric and Topological Phases with Applications to Quantum Computation

    Author : Marie Ericsson; Ignacio Cirac; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; geometric phases; topological phases; quantum computation; mixed states; completely positive maps; Fysik; Physics; Fysik; fysik; Physics;

    Abstract : Quantum phenomena related to geometric and topological phases are investigated. The first results presented are theoretical extensions of these phases and related effects. Also experimental proposals to measure some of the described effects are outlined. READ MORE

  4. 2. Open Quantum Systems : Effects in Interferometry, Quantum Computation, and Adiabatic Evolution

    Author : Johan Åberg; Erik Sjöqvist; Sten Lunell; Vlatko Vedral; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; Open Systems; Completely Positive Maps; Channels; Decoherence; Quantum Information; Quantum Computing; Adiabatic Approximation; Quantum Search; Time-Complexity; Fysik; Physics; Fysik;

    Abstract : The effects of open system evolution on single particle interferometry, quantum computation, and the adiabatic approximation are investigated.Single particle interferometry: Three concepts concerning completely positive maps (CPMs) and trace preserving CPMs (channels), named subspace preserving (SP) CPMs, subspace local channels, and gluing of CPMs, are introduced. READ MORE

  5. 3. Quantum Holonomies : Concepts and Applications to Quantum Computing and Interferometry

    Author : David Kult; Erik Sjöqvist; Gunnar Björk; Barry Sanders; Uppsala universitet; []
    Keywords : Physics; Quantum Holonomy; Geometric Phase; Quantum Computation; Completely Positive Map; Mixed State; Interferometry; Fysik;

    Abstract : Quantum holonomies are investigated in different contexts.A geometric phase is proposed for decomposition dependent evolution, where each component of a given decomposition of a mixed state evolves independently. It is shown that this geometric phase only depends on the path traversed in the space of decompositions. READ MORE