Optimal realizations of simplified Toffoli gates Academic Article uri icon


  • A simplified Toffoli gate coincides with the Toffoli gate except that the result is allowed to differ on one computational basis state by a phase factor. We prove that the simplified Toffoli gate implementation by Margolus is optimal, in the sense that it attains a lower bound of {em three} controlled-not gates, and subject to that, a sharp lower bound of {em four} single-qubit gates. We also discuss optimal implementations of other simplified Toffoli gates, and explain why the phase factor $-1$ invariably occurs in such implementations.

published proceedings


author list (cited authors)

  • Song, G., & Klappenecker, A.

citation count

  • 6

complete list of authors

  • Song, G||Klappenecker, A

publication date

  • September 2004