arXiv:1405.5361 · Physical Review Letters

Continuous-Variable Quantum Computing in Optical Time-Frequency Modes Using Quantum Memories

Peter C. Humphreys, W. Steven Kolthammer, Joshua Nunn, Marco Barbieri, Animesh Datta, Ian A. Walmsley

Published Sep 25, 2014• 65 citations

Abstract

We develop a scheme for time-frequency encoded continuous-variable cluster-state quantum computing using quantum memories. In particular, we propose a method to produce, manipulate, and measure two-dimensional cluster states in a single spatial mode by exploiting the intrinsic time-frequency selectivity of Raman quantum memories. Time-frequency encoding enables the scheme to be extremely compact, requiring a number of memories that are a linear function of only the number of different frequencies in which the computational state is encoded, independent of its temporal duration. We therefore show that quantum memories can be a powerful component for scalable photonic quantum information processing architectures.

DOI: 10.1103/physrevlett.113.130502

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