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arXiv · 2503.15869

Beam Spliter and Localization Induced by Controlled Perturbations after Time Boundary

Jing Wang·Yuetao Chen·Shaoyan Gao
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Abstract

The recent investigation into the phenomena of refraction and reflection at temporal boundaries, conducted through the lens of spacetime duality, has attracted considerable scholarly interest. This duality unveils insights into the propagation behaviors of beams at the temporal boundaries of perturbed systems. We have delineated a temporal boundary effect amenable to external control through a specifically tailored driving force, augmented by a time-varying constituent within the driving signal. We then unveil the phenomenon of beam splitting-both in time refraction and reflection induced by perturbing the lattice's hopping parameter over time. By introducing varying intensities of aperiodic disorder to the coupling coefficients, we have exercised authority over the reflection angles. Our results lay the groundwork for delving into the temporal evolution of crystalline attributes via temporal boundary effects, while also enabling deliberate manipulation of spatial distribution frequency patterns by regulating the form and magnitude of noise. The results offer a manageable avenue for scrutinizing condensed-matter phenomena through providing an experimentally feasible solution.

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Jing Wang, Yuetao Chen, Shaoyan Gao. 2025-03-20. Beam Spliter and Localization Induced by Controlled Perturbations after Time Boundary. https://arxiv.org/abs/2503.15869

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