We report the experimental demonstration of a one-way quantum protocol
reliably operating in the presence of decoherence. Information is protected by
designing an appropriate decoherence-free subspace for a cluster state
resource. We demonstrate our scheme in an all-optical setup, encoding the
information into the polarization states of four photons. A measurement-based
one-way information-transfer protocol is performed with the photons exposed to
severe symmetric phase-damping noise. Remarkable protection of information is
accomplished, delivering nearly ideal outcomes.Comment: 5 pages, 3 figures, RevTeX