近日，美国纽约城市大学的Andrea Alù及其研究小组取得一项新进展。经过不懈努力，他们通过时间界面上光子碰撞控制宽带相干波。相关研究成果已于2023年8月14日在国际知名学术期刊《自然—物理学》上发表。

该研究团队基于支持光子瞬时非保守散射事件的时间界面，探索了这种现象的时间模拟。基于这一机制，研究人员展示了具有相位可调弹性特征的超宽带时间相干波控制和机械碰撞的光子模拟。研究人员通过适当地调整反向传播信号的幅度和相位，应用它们来擦除、增强和重塑任意脉冲。这一研究结果提供了一种途径，在超快和低能量的平台上，用光有效地雕刻宽带光，而不需要空间边界。

据悉，相干波控制利用系统上多个波之间的相互干扰，根据信号的相对相位和幅值来抑制或增强输出信号。这个过程本质上是利用波之间的能量交换和空间界面来调整它们的散射，从而实现信号的调控。

附：英文原文

Title: Broadband coherent wave control through photonic collisions at time interfaces

Author: Galiffi, Emanuele, Xu, Gengyu, Yin, Shixiong, Moussa, Hady, Radi, Younes, Alù, Andrea

Issue&Volume: 2023-08-14

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 the combination of energy exchanges among the waves and spatial interfaces to tailor their scattering. Here we explore the temporal analogue of this phenomenon, based on time interfaces that support instantaneous non-conservative scattering events for photons. Based on this mechanism, we demonstrate ultrabroadband temporal coherent wave control and the photonic analogue of mechanical collisions with phase-tunable elastic features. We 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.

DOI: 10.1038/s41567-023-02165-6

Source: https://www.nature.com/articles/s41567-023-02165-6