Error Rate of the Kane Quantum Computer CNOT Gate in the Presence of   Dephasing
  We study the error rate of CNOT operations in the Kane solid state quantum computer architecture. A spin Hamiltonian is used to describe the system. Dephasing is included as exponential decay of the off diagonal elements of the system's density matrix. Using available spin echo decay data, the CNOT error rate is estimated at approsimately 10^{-3}. 
Austin G. Fowler, Cameron J. Wellard and Lloyd C.L. Hollenberg