Quantum Information Processing

, Volume 13, Issue 8, pp 1893–1905 | Cite as

Estimations of phonon-induced decoherence in silicon–germanium triple quantum dots



The decoherence and dephasing rate of charge qubits in systems based on double and triple SiGe quantum dots are studied. At the short time limit, electron–phonon interaction causes an incomplete decay of the off-diagonal density matrix elements. Long-time relaxation decay dominates over dephasing at large times. The triple quantum dot system with the same interdot distance demonstrates lower relaxation rate in the wide range of parameters.


Quantum computation Nanotechnology Quantum dots  Phonons Charge qubit Decoherence 


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  1. 1.NIXMoscowRussia
  2. 2.Institute of Physics and TechnologyRussian Academy of SciencesMoscowRussia
  3. 3.Dept. of Theoretical PhysicsMoscow Institute of Physics and TechnologyDolgoprudnyRussia

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