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arXiv · 2004.12863

Unconditional accumulation of nonclassicality in a single-atom mechanical oscillator

L. Podhora·T. Pham·A. Lešundák·P. Obšil·M. Čížek·O. Číp·P. Marek·L. Slodička·R. Filip
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Abstract

We report on the robust experimental accumulation of nonclassicallity of motion of a single trapped ion. The nonclassicality stems from deterministic incoherent modulation of thermal phonon number distribution implemented by a laser excitation of nonlinear coupling between the ion's internal - electronic levels and external - motional states. We demonstrate that the repetitive application of this nonlinear process monotonically accumulates the observable state nonclassicality. The output states converge to a phonon number distribution with high overlap with a particular Fock state and visible quantum non-Gaussian aspects including corresponding negative Wigner function. The resulting oscillator states prove deterministic transition in the hierarchy of quantum non-Gaussianity up to four phonons. This transition is very robust against experimental imperfections and produces increasing entanglement potential.

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L. Podhora, T. Pham, A. Lešundák, P. Obšil, M. Čížek, O. Číp, P. Marek, L. Slodička, R. Filip. 2020-04-27. Unconditional accumulation of nonclassicality in a single-atom mechanical oscillator. https://arxiv.org/abs/2004.12863

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