Continuous quantum measurement of a double dot

  title={Continuous quantum measurement of a double dot},
  author={Alexander N. Korotkov},
  journal={Physical Review B},
  • A. Korotkov
  • Published 15 August 1999
  • Physics
  • Physical Review B
We consider the continuous measurement of a double quantum dot by a weakly coupled detector ~tunnel point contact nearby!. While the conventional approach describes the gradual system decoherence due to the measurement, we study the situation when the detector output is explicitly recorded that leads to the opposite effect: gradual purification of the double-dot density matrix. The nonlinear Langevin equation is derived for the random evolution of the density matrix which is reflected and… 

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