We propose a new repeat-until-success (RUS) measurement-based scheme to implement quantum controlled phase gates according to the effect of dipole-induced-transparency (DIT) in a cavity and single-photon interference at a 50:50 beam-splitter. In our scheme, the DIT effect can appropriately attach a photon to the state of the dipoles according to their initial state, and in this way, a suitably encoded dipole-photon state is thus prepared. The measurement of the photon after it passing through a 50:50 beam-splitter can project the encoded matter-photon state to either a desired phase gate operation for the matter qubits or to their initial states. The recurrence of the initial state permits us to implement the desired entangling gate in a RUS way.
© 2009 Chinese Optics Letters
Decun Li, Chunlan Han, and Xunli Feng, "Repeat-until-success measurement-based scheme for controlled phase gates in a cavity," Chin. Opt. Lett. 7, 82-84 (2009)