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Error models for mode-mismatch in linear optics quantum computing

Peter P. Rohde·Timothy C. Ralph
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Abstract

One of the most significant challenges facing the development of linear optics quantum computing (LOQC) is mode-mismatch, whereby photon distinguishability is introduced within circuits, undermining quantum interference effects. We examine the effects of mode-mismatch on the parity (or fusion) gate, the fundamental building block in several recent LOQC schemes. We derive simple error models for the effects of mode-mismatch on its operation, and relate these error models to current fault tolerant threshold estimates.

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Peter P. Rohde, Timothy C. Ralph. 2006-02-01. Error models for mode-mismatch in linear optics quantum computing. https://doi.org/10.1103/physreva.73.062312

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