2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/90898We report the realization, using nuclear magnetic resonance techniques, of the first quantum computer that reliably executes an algorithm in the presence of strong decoherence. The computer is based on a quantum error avoidance code that protects against a class of multiple-qubit errors. The code stores two decoherence-free logical qubits in four noisy physical qubits. The computer successfully executes Grover's search algorithm in the presence of arbitrarily strong engineered decoherence. A control computer with no decoherence protection consistently fails under the same conditions.5 pages with 3 figures, revtex4, accepted by Physical Review Letters; v2 minor revisions to contentQuantum Physicstext