Progressive field-state collapse and quantum non-demolition photon counting

  title={Progressive field-state collapse and quantum non-demolition photon counting},
  author={Christine Guerlin and Julien Bernu and Samuel Deleglise and Cl{\'e}ment Sayrin and S. Gleyzes and Stefan Kuhr and M. Brune and Jean-Michel Raimond and Serge Haroche},
The irreversible evolution of a microscopic system under measurement is a central feature of quantum theory. From an initial state generally exhibiting quantum uncertainty in the measured observable, the system is projected into a state in which this observable becomes precisely known. Its value is random, with a probability determined by the initial system’s state. The evolution induced by measurement (known as ‘state collapse’) can be progressive, accumulating the effects of elementary state… 

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Generation and reconstruction of schrödinger cat states of light in a cavity by quantum nondemolition measurements

  • I. DotsenkoS. Deleglise S. Haroche
  • Physics
    CLEO/Europe - EQEC 2009 - European Conference on Lasers and Electro-Optics and the European Quantum Electronics Conference
  • 2009
The quantum nondemolition (QND) method for photon counting, recently developed at ENS [1,2], can be used for determining the photon number distribution of a light field by repeating the measurement

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