Bloch-sphere approach to correlated noise in coupled qubits

  title={Bloch-sphere approach to correlated noise in coupled qubits},
  author={H{\aa}kon Brox and Joakim Bergli and Yuri M. Galperin},
  journal={Journal of Physics A: Mathematical and Theoretical},
In order to demonstrate a generalized Bloch-sphere approach for the treatment of noise in coupled qubits, we perform a case study of the decoherence of a system composed of two interacting qubits in a noisy environment. In particular, we investigate the effects of correlations in the noise acting on distinct qubits. Our treatment of the two-qubit system by use of the generalized Bloch vector leads to tractable analytic equations for the dynamics of the four-level Bloch vector and allows for the… 

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