Joint qubit observables induced by indirect measurements in cavity QED

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Détails bibliographiques
Auteurs principaux:	Raikisto, Kalle, Luoma, Kimmo
Format:	Preprint
Publié:	2024
Sujets:	Quantum Physics
Accès en ligne:	Acceder al recurso
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author	Raikisto, Kalle Luoma, Kimmo
author_facet	Raikisto, Kalle Luoma, Kimmo
contents	A fundamental feature of quantum mechanics is that there are observables which can be measured jointly only when some noise is added to them. Their sharp versions are said to be incompatible. In this work we investigate time-continuous joint qubit observables induced by a indirect time-continuous measurements. In particular we study a paradigmatic situation where a qubit is interacting with a mode of light in a cavity and the light escaping the cavity is continuously monitored. We find that the properties of the qubit observables can be tuned by changing the type of the monitoring scheme or by tuning the initial state of the cavity. We observe that homodyning two orthogonal quadratures produces an optimal pair of biased jointly measurable qubit observables.
format	Preprint
id	arxiv_https___arxiv_org_abs_2406_13403
institution	arXiv
publishDate	2024
record_format	arxiv
spellingShingle	Joint qubit observables induced by indirect measurements in cavity QED Raikisto, Kalle Luoma, Kimmo Quantum Physics A fundamental feature of quantum mechanics is that there are observables which can be measured jointly only when some noise is added to them. Their sharp versions are said to be incompatible. In this work we investigate time-continuous joint qubit observables induced by a indirect time-continuous measurements. In particular we study a paradigmatic situation where a qubit is interacting with a mode of light in a cavity and the light escaping the cavity is continuously monitored. We find that the properties of the qubit observables can be tuned by changing the type of the monitoring scheme or by tuning the initial state of the cavity. We observe that homodyning two orthogonal quadratures produces an optimal pair of biased jointly measurable qubit observables.
title	Joint qubit observables induced by indirect measurements in cavity QED
topic	Quantum Physics
url	https://arxiv.org/abs/2406.13403

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