Sökning: "quantum decoherence"

Visar resultat 1 - 5 av 26 avhandlingar innehållade orden quantum decoherence.

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

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

    Sammanfattning : 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. LÄS MER

  3. 2. Quantum error correction

    Författare :Jonas Almlöf; Gunnar Björk; Jan-Åke Larsson; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; quantum error correction; dissipative channel; decoherence; fidelity; mutual information;

    Sammanfattning : This thesis intends to familiarise the reader with quantum error correction, and also show some relations to the well known concept of information - and the lesser known quantum information. Quantum information describes how information can be carried by quantum states, and how interaction with other systems give rise to a full set of quantum phenomena, many of which have no correspondence in classical information theory. LÄS MER

  4. 3. Photonic quantum information and experimental tests of foundations of quantum mechanics

    Författare :Magnus Rådmark; Mohamed Bourennane; John Rarity; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Quantum information; quantum optics; foundations of quantum mechanics; entanglement; non-contextuality; Kochen-Specker theorem; parametric down-conversion; quantum state engineering; Physics; Fysik; fysik; Physics;

    Sammanfattning : Entanglement is a key resource in many quantum information schemes and in the last years the research on multi-qubit entanglement has drawn lots of attention. In this thesis the experimental generation and characterisation of multi-qubit entanglement is presented. Specifically we have prepared entangled states of up to six qubits. LÄS MER

  5. 4. Resonances, dissipation and decoherence in exotic and artificial atoms

    Författare :Mikhail Genkin; Eva Lindroth; Lars Bojer Madsen; Stockholms universitet; []
    Nyckelord :quantum dissipation; quantum decoherence; open quantum systems; resonances; fysik; Physics;

    Sammanfattning : There are several reasons why exotic and artificial atoms attract the interest of different scientific communities.In exotic atoms, matter and antimatter can coexist for surprisingly long times. Thus, they present a unique natural laboratory for high precision antimatter studies. LÄS MER

  7. 5. The Single Cooper Pair Box - a Quantum-Mechanical Electronic Circuit

    Författare :David Gunnarsson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; quantum capacitance; quantum computing; single Cooper-pair box; SET; radio-frequency single-electron-transistor; macroscopic quantum coherence; Qubit;

    Sammanfattning : In this thesis the single Cooper pair box (SCB) is investigated with a radio frequency single electron transistor (RF-SET). The RF-SET is used as an electrometer to detect the charge of the SCB. The SCB can be regarded as a quantum two-level system and could therefore be a possible qubit. LÄS MER