2009/03/31 by Radu Ionicioiu, Timothy P. Spiller, William J. Munro
Computer Science · Physics and Astronomy · #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum and electron transport phenomena #quant-ph
paper · pdf · doi:10.1103/physreva.80.012312
published as Phys. Rev. A 80, 012312 (2009) · 5 pages, 3 figs
openalex publication_date 2009/07/13 · arxiv created 2009/07/15 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present quantum networks for a n-qubit controlled gate C^n\ensuremath-1(U) which use a higher-dimensional (qudit) ancilla as a catalyzer. In its simplest form the network has only n two-particle gates (qubit-qudit)---this is the minimum number of two-body interactions needed to couple all n+1 subsystems (n qubits plus one ancilla). This class of controlled gates includes the generalized Toffoli gate C^n\ensuremath-1(X) on n qubits, which plays an important role in several quantum algorithms and error correction. A particular example implementing this model is given by the dispersive limit of a generalized Jaynes-Cummings Hamiltonian of an effective spin s interacting with a cavity mode.