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arXiv · 2307.04877

Engineering bound states in continuum via nonlinearity induced extra dimension

Qingtian Miao·Jayakrishnan M. P. Nair·Girish S. Agarwal
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Abstract

Bound states in continuum (BICs) are localized states of a system possessing significantly large life times with applications across various branches of science. In this work, we propose an expedient protocol to engineer BICs which involves the use of Kerr nonlinearities in the system. The generation of BICs is a direct artifact of the nonlinearity and the associated expansion in the dimensionality of the system. In particular, we consider single and two mode anharmonic systems and provide a number of solutions apposite for the creation of BICs. In close vicinity to the BIC, the steady state response of the system is immensely sensitive to perturbations in natural frequencies of the system and we illustrate its propitious sensing potential in the context of experimentally realizable setups for both optical and magnetic nonlinearities.

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Qingtian Miao, Jayakrishnan M. P. Nair, Girish S. Agarwal. 2023-07-10. Engineering bound states in continuum via nonlinearity induced extra dimension. https://doi.org/10.1103/physrevresearch.5.043053

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