Realization of a General Three-Qubit Quantum Gate
Farrokh Vatan, Colin P. Williams · arXiv (Cornell University) · 2004
We prove that a generic three-qubit quantum logic gate can be implemented using at most 98 one-qubit rotations about the $y$- and $z$-axes and 40 CNOT gates, beating an earlier bound of 64 CNOT gates.