A solid-state NMR three-qubit homonuclear system for quantum information   processing: control and characterization
  A three-qubit 13C solid-state nuclear magnetic resonance (NMR) system for quantum information processing, based on the malonic acid molecule, is used to demonstrate high-fidelity universal quantum control via strongly-modulating radio-frequency pulses. This control is achieved in the strong-coupling regime, in which the timescales of selective qubit addressing and of two-qubit interactions are comparable. 
Jonathan Baugh, Osama Moussa, Colm A. Ryan, Raymond Laflamme,   Chandrasekhar Ramanathan, Timothy F. Havel, David G. Cory