Quantum-State Tomography and Quantum Communication

  • Ulf Leonhardt
  • Igor Jex
Conference paper


The possibility to reconstruct a quasiprohability distribution1 from measured data attracted considerable interest in recent years. Following the proposal of Vogel and Risken2 the experimental feasibility of this scheme was demonstrated3. By measuring the rotated quadratures of a single-mode field we can reconstruct. the initial state to be measured, and in this way retrieve the full information eventually encoded in the initial state. In the case, we want, to employ a quantum system to transfer information, a. finite quantum system might be a better choice then an infinite-dimensional single mode system. In such a scheme an emitter (Alice) encodes the information on a finite quantum system and this is transferred to the observer (Bob). When Bob does not have at hand the decoding method he can still relay on the tomography approach. In the following we shortly demonstrate how this might work. Let, us note, that we do not claim. that the method is evesdropper safe.


Density Operator Wigner Function Quantum Communication Tomography Approach Spin Particle 
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Copyright information

© Springer Science+Business Media New York 1996

Authors and Affiliations

  • Ulf Leonhardt
    • 1
    • 2
  • Igor Jex
    • 1
    • 3
  1. 1.Arbeitsgruppe “Nicht klassische Strahlung”Max-Planck Gesellschaft an der Humboldt Universität BerlinBerlinGermany
  2. 2.Department of Physics and Chemical Physics InstituteUniversity of OregonEugeneUSA
  3. 3.Institute of Physics. SASBratislavaSlovakia

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