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arXiv · 2203.08281

Topological Modes in a Laser Cavity through Exceptional State Transfer

A. Schumer·Y. G. N. Liu·J. Leshin·L. Ding·Y. Alahmadi·A. U. Hassan·H. Nasari·S. Rotter·D. N. Christodoulides·P. LiKamWa·M. Khajavikhan
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Abstract

Shaping the light emission characteristics of laser systems is of great importance in various areas of science and technology. In a typical lasing arrangement, the spatial profile of the mode tends to remain self-similar throughout the cavity. Here, we introduce a paradigm shift where a spatially evolving mode is faithfully settled into a pair of bi-orthogonal states at the two facets of a laser cavity. This is achieved by deliberately eliminating non-adiabatic jumps in a purposely designed structure that features a dynamic encirclement of a non-Hermitian exceptional point. The resulting state transfer reflects the unique topology of the associated Riemann surfaces. Our approach provides a route to develop versatile mode selective active

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A. Schumer, Y. G. N. Liu, J. Leshin, L. Ding, Y. Alahmadi, A. U. Hassan, H. Nasari, S. Rotter, D. N. Christodoulides, P. LiKamWa, M. Khajavikhan. 2022-03-15. Topological Modes in a Laser Cavity through Exceptional State Transfer. https://doi.org/10.1126/science.abl6571

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