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arXiv · 1110.5583

On the qubit limit of cavity nonlinear optics

Hideo Mabuchi
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Abstract

Many proposals for solid-state photonic implementations of quantum information processing utilize high-quality optical resonators to achieve strong coupling between guided fields and heterogeneously incorporated qubits. Given the practical difficulty of accurately placing quantum dots, vacancy centers, or other such atom-like emitters throughout a complex nanophotonic circuit, it would be natural to consider whether high-quality resonators could be used in conjunction with bulk optical nonlinearities to create optically-coupled qubit degrees of freedom via lithographic patterning of a homogeneous medium. A recent limit theorem for quantum stochastic differential equations can be used to prove rigorously that this should be possible, in principle, using resonators incorporating a strongly Kerr-nonlinear, $χ^{(2)}$-nonlinear, or two-photon absorbing material with very low loss at the fundamental optical wavelength.

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Hideo Mabuchi. 2011-12-30. On the qubit limit of cavity nonlinear optics. https://doi.org/10.1103/physreva.85.015806

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