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Quantum noise in ideal operational amplifiers

Jean-Michel Courty·Francesca Grassia·Serge Reynaud
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Abstract

We consider a model of quantum measurement built on an ideal operational amplifier operating in the limit of infinite gain, infinite input impedance and null output impedance and with a feddback loop. We evaluate the intensity and voltage noises which have to be added to the classical amplification equations in order to fulfill the requirements of quantum mechanics. We give a description of this measurement device as a quantum network scattering quantum fluctuations from input to output ports.

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Jean-Michel Courty, Francesca Grassia, Serge Reynaud. 1998-11-24. Quantum noise in ideal operational amplifiers. https://doi.org/10.1209/epl/i1999-00558-3

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