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arXiv · 0804.0603

Ground state cooling of a nanomechanical resonator via a Cooper pair box qubit

Konstanze Jaehne·Klemens Hammerer·Margareta Wallquist
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Abstract

In this paper we present a scheme for ground state cooling of a flexural mode of a nanomechanical beam incorporated in a loop-shaped Cooper-pair box (CPB) circuit. Via the Lorentz force coupling of the beam motion to circulating CPB-circuit currents, energy is transferred to the CPB qubit which acts as a dissipative two-level system. The cooling process is driven by a detuned gate-voltage drive acting on the CPB. We analyze the cooling force spectrum and present analytical expressions for the cooling rate and final occupation number for a wide parameter regime. In particular, we find that cooling is optimized in a strong drive regime, and we present the necessary conditions for ground-state cooling.

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Konstanze Jaehne, Klemens Hammerer, Margareta Wallquist. 2008-09-18. Ground state cooling of a nanomechanical resonator via a Cooper pair box qubit. https://doi.org/10.1088/1367-2630%2F10%2F9%2F095019

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