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arXiv · 2112.04850

The quantum Zeno and anti-Zeno effects in the strong coupling regime

Ghazi Khan·Hudaiba Soomro·Muhammad Usman Baig·Irfan Javed·Adam Zaman Chaudhry
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Abstract

It is well known that repeated projective measurements can either speed up (the Zeno effect) or slow down (the anti-Zeno effect) quantum evolution. Until now, however, studies of these effects for a two-level system interacting strongly with its environment have focused on repeatedly preparing the excited state of the two-level system via the projective measurements. In this paper, we consider the repeated preparation of an arbitrary state of a two-level system that is interacting strongly with an environment of harmonic oscillators. To handle the strong interaction, we perform a polaron transformation, and thereafter use a perturbative approach to calculate the decay rates for the system. Upon calculating the decay rates, we discover that there is a transition in their qualitative behaviors as the state being repeatedly prepared moves away from the excited state towards a superposition of the ground and excited states. Our results should be useful for the quantum control of a two-level system interacting with its environment.

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Ghazi Khan, Hudaiba Soomro, Muhammad Usman Baig, Irfan Javed, Adam Zaman Chaudhry. 2021-12-09. The quantum Zeno and anti-Zeno effects in the strong coupling regime. https://arxiv.org/abs/2112.04850

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