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Laser Physics

, Volume 16, Issue 11, pp 1512–1516 | Cite as

Kraus representation for the density operator of a qubit

  • D. M. Tong
  • J. L. Chen
  • J. Y. Huang
  • L. C. Kwek
  • C. H. Oh
Quantum Information and Quantum Computation

Abstract

We show that the time evolution of the density operator of a qubit can always be described in terms of the Kraus representation. A general scheme on how to construct the Kraus operators for an open qubit system is proposed, which can be generalized to open higher dimensional quantum systems.

PACS numbers

03.65.Yz 03.65.Ca 

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Copyright information

© MAIK “Nauka/Interperiodica” 2006

Authors and Affiliations

  • D. M. Tong
    • 1
  • J. L. Chen
    • 1
  • J. Y. Huang
    • 2
  • L. C. Kwek
    • 1
    • 3
  • C. H. Oh
    • 1
  1. 1.Department of PhysicsNational University of SingaporeSingapore
  2. 2.Wuxi Institute of TechnologyUniversity CityWuxiPRC
  3. 3.National Institute of EducationNanyang Technological UniversitySingapore

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