  We construct a new error-suppression scheme that makes use of the adjoint of
reversible quantum algorithms. For decoherence induced errors such as
depolarization, it is presented that provided the depolarization error
probability is less than 1, our scheme can exponentially reduce the final
output error rate to zero using a number of cycles, and the output state can be
coherently sent to another stage of quantum computation process. Besides,
experimental set-ups via optical approach have been proposed using Grover's
search algorithm as an example. Some further discussion on the benefits and
limitations of the scheme is given in the end.
