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arXiv · 2212.02647

Broadband Coherent Wave Control Through Photonic Collisions at Time Interfaces

Emanuele Galiffi·Gengyu Xu·Shixiong Yin·Hady Moussa·Younes Radi·Andrea Alù
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Abstract

Coherent wave control exploits the interference among multiple waves impinging on a system to suppress or enhance outgoing signals based on their relative phase and amplitude. This process inherently requires non-Hermiticity, in order to enable energy exchanges among the waves, and spatial interfaces in order to tailor their scattering. Here we explore the temporal analogue of this phenomenon, based on time-interfaces that support instantaneous non-Hermitian scattering events for photons analogous to mechanical collisions. Based on this mechanism, we demonstrate ultra-broadband temporal coherent wave control and photonic collisions with phase-tunable elastic features, and apply them to erase, enhance and reshape arbitrary pulses by suitably tailoring the amplitude and phase of counterpropagating signals. Our findings provide a pathway to effectively sculpt broadband light with light without requiring spatial boundaries, within an ultrafast and low-energy platform.

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Emanuele Galiffi, Gengyu Xu, Shixiong Yin, Hady Moussa, Younes Radi, Andrea Alù. 2022-12-05. Broadband Coherent Wave Control Through Photonic Collisions at Time Interfaces. https://arxiv.org/abs/2212.02647

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