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arXiv · 0808.0743

Kerr nonlinearities and nonclassical states with superconducting qubits and nanomechanical resonators

F. L. Semião·K. Furuya·G. J. Milburn
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Abstract

We propose the use of a superconducting charge qubit capacitively coupled to two resonant nanomechanical resonators to generate Yurke-Stoler states, i.e. quantum superpositions of pairs of distinguishable coherent states 180$^\circ$ out of phase with each other. This is achieved by effectively implementing Kerr nonlinearities induced through application of a strong external driving field in one of the resonators. A simple study of the effect of dissipation on our scheme is also presented, and lower bounds of fidelity and purity of the generated state are calculated. Our procedure to implement a Kerr nonlinearity in this system may be used for high precision measurements in nanomechanical resonators.

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F. L. Semião, K. Furuya, G. J. Milburn. 2008-08-05. Kerr nonlinearities and nonclassical states with superconducting qubits and nanomechanical resonators. https://doi.org/10.1103/physreva.79.063811

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