Quantum Information Processing

, Volume 1, Issue 3, pp 207–224 | Cite as

On the Generation of Sequential Unitary Gates from Continuous Time Schrödinger Equations Driven by External Fields

  • Claudio Altafini


In most of the proposals for quantum computers, a common feature is that the quantum circuits are expected to be made of cascades of unitary transformations acting on the quantum states. Such unitary gates are normally assumed to belong to a given discrete set of transformations. However, arbitrary superposition of quantum states may be achieved by utilizing a fixed number of transformations, each depending on a parameter. A framework is proposed to dynamically express these parameters directly in terms of the control inputs entering into the continuous time forced Schrouml;dinger equation.

PACS: 03.67.Lx; 03.65.Fd; 02.30.Mv; 02.30.Xy

quantum control quantum circuits driven Schrödinger equation Wei-Norman formula product of exponentials 


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Copyright information

© Plenum Publishing Corporation 2002

Authors and Affiliations

  • Claudio Altafini
    • 1
  1. 1.SISSA-ISASInternational School for Advanced StudiesTriesteItaly

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