Protecting multi-qubit states in computational subspaces by nested dynamical decoupling sequences
Nan Qiu, Jiangbin Gong, Xiang‐Bin Wang · Journal of Physics B Atomic Molecular and Optical Physics · 2012
We propose to nest 3M layers of explicitly constructed Uhrig?s dynamical decoupling sequences of local control operators to achieve universal high-order protection of arbitrary and unknown M-qubit states on a 2M-dimensional computational subspace. This is the case even if the mechanism responsible for population leakage from the computational subspace is unclear and the actual form of system?environment coupling is not given. Simple numerical experiments are carried out to illustrate our theoretical proposal.