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arXiv · 2506.07800

In-situ tuning of cavity dissipation and a topological transition in an atom-nanotip-cavity system

Taegyu Ha·Kiyanoush Goudarzi·Dowon Lee·Donggeon Kim·Eunchul Jeong·Uijin Kim·Myunghun Kim·Jinuk Kim·Moonjoo Lee
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Abstract

We theoretically investigate a method for tuning a dissipation rate in an atom-cavity system. By inserting a nanotip into the cavity mode, we estimate that the cavity dissipation rate increases by a factor of approximately 20, due to the scattering loss at the tip. As applications of our in-situ technique, we demonstrate that an exceptional line can be obtained when a single atom or ion is coupled to the resonator. Moreover, the position of an exceptional point is tuned by adjusting the decay rate, enabling a topological transition through dissipation control alone.

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Taegyu Ha, Kiyanoush Goudarzi, Dowon Lee, Donggeon Kim, Eunchul Jeong, Uijin Kim, Myunghun Kim, Jinuk Kim, Moonjoo Lee. 2025-06-09. In-situ tuning of cavity dissipation and a topological transition in an atom-nanotip-cavity system. https://arxiv.org/abs/2506.07800

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