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Quantum transducers: Integrating Transmission Lines and Nanomechanical Resonators via Charge Qubits

C. P. Sun·L. F. Wei·Yu-xi Liu·Franco Nori
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Abstract

We propose a mechanism to interface a transmission line resonator (TLR) with a nano-mechanical resonator (NAMR) by commonly coupling them to a charge qubit, a Cooper pair box with a controllable gate voltage. Integrated in this quantum transducer or simple quantum network, the charge qubit plays the role of a controllable quantum node coherently exchanging quantum information between the TLR and NAMR. With such an interface, a maser-like process is predicted to create a quasi-classical state of the NAMR by controlling a single-mode classical current in the TLR. Alternatively, a "Cooper pair" coherent output through the transmission line can be driven by a single-mode classical oscillation of the NAMR.

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C. P. Sun, L. F. Wei, Yu-xi Liu, Franco Nori. 2005-04-08. Quantum transducers: Integrating Transmission Lines and Nanomechanical Resonators via Charge Qubits. https://doi.org/10.1103/physreva.73.022318

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