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Qubit Assisted Probing of Coherence Between States of a Macroscopic Apparatus

Sougato Bose
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Abstract

I present a general scheme through which the evidence of a superposition involving distinct classical-like states of a macroscopic system can be probed. The scheme relies on a qubit being coupled to a macroscopic harmonic oscillator in such a way that it can be used to both prepare and probe a macroscopic superposition. Two potentially realizable implementations, one with a flux qubit coupled to a LC circuit, and the other with an ion-trap qubit coupled to the collective motion of several ions, are proposed.

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Sougato Bose. 2003-08-22. Qubit Assisted Probing of Coherence Between States of a Macroscopic Apparatus. https://arxiv.org/abs/quant-ph/0308122

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