  Scalable quantum computing can only be achieved if qubits are manipulated
fault-tolerantly. Topological error correction - a novel method which combines
topological quantum computing and quantum error correction - possesses the
highest known tolerable error rate for a local architecture. This scheme makes
use of cluster states with topological properties and requires only
nearest-neighbour interactions. Here we report the first experimental
demonstration of topological error correction with an eight-photon cluster
state. It is shown that a correlation can be protected against a single error
on any qubit, and when all qubits are simultaneously subjected to errors with
equal probability, the effective error rate can be significantly reduced. This
demonstrates the viability of topological error correction. Our work represents
the first experimental effort to achieve fault-tolerant quantum information
processing by exploring the topological properties of quantum states.
