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arXiv · 1904.06967

Optical waveguide hosting multiple exceptional points: Toward selective mode conversion

Arnab Laha·Harsh K. Gandhi·Sibnath Dey·Sayan Bhattacherjee·Abhijit Biswas·Somnath Ghosh
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Abstract

We investigate the astonishing physical aspects of Exceptional Points (EPs) in a 1D planar few-mode optical waveguide. The waveguide hosts four quasi-guided modes. Here interactions between the selected pair of modes are modulated by a spatial distribution of inhomogeneous gain-loss profile. Both the coupled pairs approach two different second-order EPs in parameter plane. Considering a proper parametric loop to encircle the identified EPs simultaneously, we establish a specific topological feature where one round encirclement in parameter space yields the switching between the propagation constants ({\beta}) of the corresponding pairs of couple modes in complex {\beta}-plane. Choosing two different patterns of the parametric loop, we establish the immutable topology in {\beta}- switching phenomena. This robust mode conversion scheme shall provide a platform to realize selective mode switching devices or optical-mode converters.

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Arnab Laha, Harsh K. Gandhi, Sibnath Dey, Sayan Bhattacherjee, Abhijit Biswas, Somnath Ghosh. 2019-04-15. Optical waveguide hosting multiple exceptional points: Toward selective mode conversion. https://arxiv.org/abs/1904.06967

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