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arXiv · 1301.5661

Initial states of qubit-boson models leading to conserved quantities

Bartlomiej Gardas·Jerzy Dajka
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Abstract

It is possible to prepare a composite qubit-environment system so that its time evolution will guarantee the conservation of a preselected qubit's observable. In general, this observable is not associated with a symmetry. The latter may not even be present in the subsystem. The initial states which lead to such a quantity conserved dynamics form a subspace of the qubit-environment space of states. General construction of this subspace is presented and illustrated by two examples. The first one is the exactly soluble Jaynes-Cummings model and the second is the multi-photon Rabi model.

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Bartlomiej Gardas, Jerzy Dajka. 2013-05-09. Initial states of qubit-boson models leading to conserved quantities. https://doi.org/10.1088/1751-8113/46/23/235301

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