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Efficient Linear Optics Quantum Computation

E. Knill·R. Laflamme·G. Milburn
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Abstract

We investigate the computational power of passive and active linear optical elements and photo-detectors. We show that single photon sources, passive linear optics and photo-detectors are sufficient for implementing reliable quantum algorithms. Feedback from the detectors to the optical elements is required for this implementation. Without feedback, non-deterministic quantum computation is possible. A single photon source sufficient for quantum computation can be built with an active linear optical element (squeezer) and a photo-detector. The overheads associated with using only linear optics appear to be sufficiently low to make quantum computation based on our proposal a viable alternative.

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E. Knill, R. Laflamme, G. Milburn. 2000-06-20. Efficient Linear Optics Quantum Computation. https://arxiv.org/abs/quant-ph/0006088

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