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arXiv · 1811.11520

The quantum Zeno and anti-Zeno effects: from weak to strong system-environment coupling

Bilal Khalid·Adam Zaman Chaudhry
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Abstract

By repeatedly measuring a quantum system, the evolution of the system can be slowed down (the quantum Zeno effect) or sped up (quantum anti-Zeno effect). We study these effects for a single two-level system coupled to a collection of harmonic oscillators. Previously, such systems have been studied in both the weak and the strong system-environment coupling regimes. In this paper, we apply a polaron transformation in a manner that allows us to study the quantum Zeno and anti-Zeno effects for a large variety of system-environment parameters. Using this approach, we reproduce previous results for the weak and strong system-environment coupling regimes. Moreover, as long as the environment is super-Ohmic, we show how our approach can be used to explore regimes such as the moderate system-environment coupling regime that could not be investigated before in a straightforward manner.

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Bilal Khalid, Adam Zaman Chaudhry. 2018-11-28. The quantum Zeno and anti-Zeno effects: from weak to strong system-environment coupling. https://doi.org/10.1140/epjd%2Fe2019-90681-3

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