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arXiv:1305.4336 · Physical Review A

Emulating quantum cubic nonlinearity

Mitsuyoshi Yukawa, Kazunori Miyata, Hidehiro Yonezawa, Petr Marek, Radim Filip, Akira Furusawa

Published Nov 13, 2013• 78 citations
arXivHTMLPDF

Abstract

Unitary non-Gaussian nonlinearity is one of the key components required for quantum computation and other developing applications of quantum information processing. Sufficient operation of this kind is still not available, but it can be approximatively implemented with the help of a specifically engineered resource state constructed from individual photons. We present experimental realization and thorough analysis of such quantum resource states and confirm that the state does indeed possess properties of a state produced by unitary dynamics driven by cubic nonlinearity.

DOI
10.1103/physreva.88.053816

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Unitary non-Gaussian nonlinearity is one of the key components required for quantum computation and other developing applications of quantum information processing. Sufficient operation of this kind is still not available, but it can be approximatively implemented with the help of a specifically engineered resource state constructed from individual photons. We present experimental realization and thorough analysis of such quantum resource states and confirm that the state does indeed possess properties of a state produced by unitary dynamics driven by cubic nonlinearity.
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Squeezed states of the harmonic oscillator are a common resource in applications of quantum technology. If the noise is suppressed in a nonlinear combination of quadrature operators, the quantum states are non-Gaussian and we refer to the noise reduction as nonlinear squeezing. Non-Gaussian aspects of quantum states are often those most vulnerable to decoherence due to imperfections appearing in realistic experimental implementations. We analyze the behavior of quantum states with cubic nonlinear squeezing under loss and dephasing. The properties of nonlinear squeezed states depend on their initial parameters that can be optimized and adjusted to achieve the maximal robustness for the potential applications.
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Squeezed states of the harmonic oscillator are a common resource in applications of quantum technology. If the noise is suppressed in a nonlinear combination of quadrature operators below threshold for all possible up-to-quadratic Hamiltonians, the quantum states are non-Gaussian and we refer to the noise reduction as nonlinear squeezing. Non-Gaussian aspects of quantum states are often more vulnerable to decoherence due to imperfections appearing in realistic experimental implementations. Therefore, a stability of nonlinear squeezing is essential. We analyze the behavior of quantum states with cubic nonlinear squeezing under loss and dephasing. The properties of nonlinear squeezed states depend on their initial parameters which can be optimized and adjusted to achieve the maximal robustness for the potential applications.