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arXiv · 0804.2179

Probing the quantum coherence of a nanomechanical resonator using a superconducting qubit II: Implementation

M. P. Blencowe·A. D. Armour
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Abstract

We describe a possible implementation of the nanomechanical quantum superposition generation and detection scheme described in the preceding, companion paper [Armour A D and Blencowe M P 2008 New. J. Phys. Submitted]. The implementation is based on the circuit quantum electrodynamics (QED) set-up, with the addition of a mechanical degree of freedom formed out of a suspended, doubly-clamped segment of the superconducting loop of a dc SQUID located directly opposite the centre conductor of a coplanar waveguide (CPW). The relative merits of two SQUID based qubit realizations are addressed, in particular a capacitively coupled charge qubit and inductively coupled flux qubit. It is found that both realizations are equally promising, with comparable qubit-mechanical resonator mode as well as qubit-microwave resonator mode coupling strengths.

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M. P. Blencowe, A. D. Armour. 2008-04-14. Probing the quantum coherence of a nanomechanical resonator using a superconducting qubit II: Implementation. https://doi.org/10.1088/1367-2630%2F10%2F9%2F095005

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