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

Abstract

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.

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Correspondence to Leonid Fedichkin.

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Vasiliev, A.Y., Fedichkin, L. Estimations of phonon-induced decoherence in silicon–germanium triple quantum dots. Quantum Inf Process 13, 1893–1905 (2014). https://doi.org/10.1007/s11128-014-0780-4

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Keywords

  • Quantum computation
  • Nanotechnology
  • Quantum dots
  • Phonons
  • Charge qubit
  • Decoherence