title: Configurable unitary transformations and linear logic gates using quantum memories.
abstract: We show that a set of optical memories can act as a configurable linear optical network operating on frequency-multiplexed optical states. Our protocol is applicable to any quantum memories that employ off-resonant Raman transitions to store optical information in atomic spins. In addition to the configurability, the protocol also offers favorable scaling with an increasing number of modes where N memories can be configured to implement arbitrary N-mode unitary operations during storage and readout. We demonstrate the versatility of this protocol by showing an example where cascaded memories are used to implement a conditional cz gate.
authors.affiliation: Centre for Quantum Computation and Communication Technology, Department of Quantum Science, The Australian National University, Canberra, ACT 0200, Australia.
authors.forename: G T
authors.initials: GT
authors.lastname: Campbell
authors.affiliation: Centre for Quantum Computation and Communication Technology, Department of Quantum Science, The Australian National University, Canberra, ACT 0200, Australia.
authors.forename: O
authors.initials: O
authors.lastname: Pinel
authors.affiliation: Centre for Quantum Computation and Communication Technology, Department of Quantum Science, The Australian National University, Canberra, ACT 0200, Australia.
authors.forename: M
authors.initials: M
authors.lastname: Hosseini
authors.affiliation: Centre for Quantum Computation and Communication Technology, School of Mathematics and Physics, University of Queensland, Brisbane, Queensland 4072, Australia.
authors.forename: T C
authors.initials: TC
authors.lastname: Ralph
authors.affiliation: Centre for Quantum Computation and Communication Technology, Department of Quantum Science, The Australian National University, Canberra, ACT 0200, Australia.
authors.forename: B C
authors.initials: BC
authors.lastname: Buchler
authors.affiliation: Centre for Quantum Computation and Communication Technology, Department of Quantum Science, The Australian National University, Canberra, ACT 0200, Australia.
authors.forename: P K
authors.initials: PK
authors.lastname: Lam