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arXiv · 1911.12875

Virtual Parity-Time Symmetry

Huanan Li·Ahmed Mekawy·Alex Krasnok·Andrea Alù
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Abstract

Parity-time (PT) symmetry has been opening exciting opportunities in optics, yet the required careful balance of loss and gain has been hindering its practical implementations. Here, we propose a gain-free route to PT-symmetry based on non-monochromatic excitations that mimic loss and gain in passive systems. Based on the concept of virtual absorption, extended here to implement also virtual gain, we induce PT-symmetry and its landmark effects, such as broken phase transitions, anisotropic transmission resonances and laser-absorber pairs, in a fully passive, hence inherently stable, system. These results open a path to establish PT-symmetric phenomena in purely passive platforms.

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Huanan Li, Ahmed Mekawy, Alex Krasnok, Andrea Alù. 2019-11-28. Virtual Parity-Time Symmetry. https://doi.org/10.1103/physrevlett.124.193901

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