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Circuit analysis of quantum measurement

Yuji Kurotani·Masahito Ueda
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Abstract

We develop a circuit theory that enables us to analyze quantum measurements on a two-level system and on a continuous-variable system on an equal footing. As a measurement scheme applicable to both systems, we discuss a swapping state measurement which exchanges quantum states between the system and the measuring apparatus before the apparatus meter is read out. This swapping state measurement has an advantage in gravitational-wave detection over contractive state measurement in that the postmeasurement state of the system can be set to a prescribed one, regardless of the outcome of the measurement.

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Yuji Kurotani, Masahito Ueda. 2006-09-08. Circuit analysis of quantum measurement. https://doi.org/10.1103/physreva.75.012110

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