Decoherence by correlated noise and quantum error correction.
We study the decoherence of a quantum computer in an environment which is inherently correlated in time and space. We first derive the nonunitary time evolution of the computer and environment in the presence of a stabilizer error correction code, providing a general way to quantify decoherence for a quantum computer. The general theory is then applied to the spin-boson model. Our results demonstrate that effects of long-range correlations can be systematically reduced by small changes in the error correction codes.
Novais
E
E
Department of Physics, Duke University, Durham, North Carolina 27708-0305, USA.
Baranger
Harold U
HU