Stabilizing distinguishable qubits against spontaneous decay by detected-jump correcting quantum codes

A class of error-correcting quantum codes is introduced capable of stabiliz ing qubits against spontaneous decay arising from couplings to statisticall y independent reservoirs. These quantum codes are based on the idea of usin g an embedded quantum code and exploiting the classical information availab le about which qubit has been affected by the environment. They are immedia tely relevant for quantum computation and information processing using arra ys of trapped ions or nuclear spins. Interesting relations between these qu antum codes and basic notions of design theory are established.