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Direct measurement of the quantum state of the electromagnetic field in a superconducting transmission line

F. de Melo·L. Aolita·F. Toscano·L. Davidovich
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Abstract

We propose an experimental procedure to directly measure the state of an electromagnetic field inside a resonator, corresponding to a superconducting transmission line, coupled to a Cooper-pair box (CPB). The measurement protocol is based on the use of a dispersive interaction between the field and the CPB, and the coupling to an external classical field that is tuned to resonance with either the field or the CPB. We present a numerical simulation that demonstrates the feasibility of this protocol, which is within reach of present technology.

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F. de Melo, L. Aolita, F. Toscano, L. Davidovich. 2006-02-23. Direct measurement of the quantum state of the electromagnetic field in a superconducting transmission line. https://doi.org/10.1103/physreva.73.030303

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