Construction and implementation of NMR quantum logic gates for two spin systems

The implementation of small prototype quantum computers has been studied th rough ensemble quantum computing via NMR measurements. In such laboratory s tudies it is convenient to have access to a wide array of logic gates. Here a systematic approach to reduce the logic gate to an NMR pulse sequence is introduced. This approach views the truth table for a quantum logic operat ion as a permutation matrix that corresponds to a propagator for an NMR tra nsition. This propagator is then used as the starting point for the derivat ion of a pulse sequence, Pulse sequences for all the permutations of a four level system are reported along with implementations of representative exa mples on a two spin-1/2 system, C-13-labeled chloroform, (C) 1999 Academic Press.