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The Decoherence of Single Electron Quantum Dot Qubit

  • Yi-Fu Yu
  • Wei-Ping Li
  • Ji-Wen Yin
  • Jing-Lin Xiao
Article

Abstract

On the condition of electric-LO phonon strong coupling in parabolic quantum dot, we obtain the eigenenergies of the ground state and the first-excited state, the eigenfunctions of the ground state and the first-excited state by using variational method of Pekar type. This system in quantum dot may be employed as a two-level quantum system-qubit. The phonon spontaneous emission causes the decoherence of the qubit. We displayed the density matrix of the qubit decayed with the time evolution and the coherence term of the density matrix element p 10 (or p 01) decayed with the time evolution for different coupling strength, the confinement length, the coefficient dispersion.

Keywords

Quantum dot Qubit Decoherence Density matrix 

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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Yi-Fu Yu
    • 1
  • Wei-Ping Li
    • 1
  • Ji-Wen Yin
    • 1
  • Jing-Lin Xiao
    • 2
  1. 1.Department of Physic and Electronic Information EngineeringChifeng CollegeChifengChina
  2. 2.College of Physics and ElectromechanicsInner Mongolia National UniversityTongliaoChina

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