Addendum to “Grover search with pairs of trapped ions”
Zhenyu Xu, Mang Feng · Physical Review A · 2008
The authors call attention to a previous work [M. Feng, Phys. Rev. A 63, 052308 (2001)] for Grover search by trapped ions in decoherence-free subspace (DFS). A scheme for a two-qubit conditional-phase flip gate in DFS is presented as a supplement.