  A method to suppress noise, which is one of the major obstacles to obtain an
optimal solution in quantum annealers, is proposed. We generalize the
conventionally used Hamiltonian, i.e., the transverse field Hamiltonian, by
introducing an ancillary system, which leads to cancellation of the effect of
noise on the system under consideration for some typical cases. We also confirm
numerically that the method is effective for a kind of noise usually
encountered in the case of flux qubit.
