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arXiv · 1612.00942

Hybrid quantum device with a carbon nanotube and a flux qubit for dissipative quantum engineering

Xin Wang·Adam Miranowicz·Hong-Rong Li·Franco Nori
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Abstract

We describe a hybrid quantum system composed of a micrometer-size carbon nanotube (CNT) longitudinally coupled to a flux qubit. We demonstrate the usefulness of this device for generating high-fidelity nonclassical states of the CNT via dissipative quantum engineering. Sideband cooling of the CNT to its ground state and generating a squeezed ground state, as a mechanical analogue of the optical squeezed vacuum, are two additional examples of the dissipative quantum engineering studied here. Moreover, we show how to generate a long-lived macroscopically-distinct superposition (i.e., a Schr\"odinger cat-like) state. This cat state can be trapped, under some conditions, in a dark state, as can be verified by detecting the optical response of control fields.

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Xin Wang, Adam Miranowicz, Hong-Rong Li, Franco Nori. 2016-12-03. Hybrid quantum device with a carbon nanotube and a flux qubit for dissipative quantum engineering. https://doi.org/10.1103/physrevb.95.205415

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