arXiv:1308.2645 · Physical Review A

Improving photon detector efficiency using a high-fidelity optical controlled-not gate

Katherine L. Brown, R. Singh, Joshua H. Mendez, Hanna E. Broadus, Jonathan P. Dowling

Published Feb 20, 2015• 0 citations

Abstract

A significant problem for optical quantum computing is inefficient or inaccurate photodetectors. It is possible to use controlled-not (cnot) gates to improve a detector by making a large cat state, then measuring every qubit in that state. In this paper we develop a code that compares five different schemes for making multiple measurements, some of which are capable of detecting loss and some of which are not. We explore how each of these schemes performs in the presence of different errors, and derive a formula to find at what probability of qubit loss it is worth detecting loss, and at what probability does this just lead to further errors than the loss introduces.

DOI: 10.1103/physreva.91.022327

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