近日，华中科技大学的舒学文及其研究小组与香港中文大学的孙贤开合作并取得一项新进展。经过不懈努力，他们实现光子弗洛凯-布洛赫振荡的视觉观察。相关研究成果已于2024年4月28日在国际知名学生期刊《光：科学与应用》上发表。

该研究团队运用光子类比的概念，推广了现有的光子弗洛凯晶格中的布洛赫振荡（BOs），提出了“光子弗洛凯-布洛赫振荡”（FBOs）。这种振荡特指具有调制周期和布洛赫振荡周期的，扩展最小公倍数的重标度光子Bloch振荡。随后，研究人员借助波导荧光显微镜，首次成功观察到了这种独特的光子弗洛凯-布洛赫振荡。

最重要的是，FBOs超越了弗洛凯系统中现有的BOs，并表现出独特的特性，包括分形谱和分数弗洛凯隧道效应。这种新的输运机制提供了一种有趣的波操纵方法，可能有助于光子学、凝聚态物理和量子物理领域的快速发展。

据悉，布洛赫振荡(BOs)是一种重要的输运现象，在静态系统中得到了广泛的研究，但在弗洛凯系统中仍然是一个谜。

附：英文原文

Title: Visual observation of photonic Floquet–Bloch oscillations

Author: Zhang, Zhen, Li, Yuan, Sun, Xiankai, Shu, Xuewen

Issue&Volume: 2024-04-28

Abstract: Bloch oscillations (BOs), an important transport phenomenon, have been studied extensively in static systems but remain mysterious in Floquet systems. Here, by harnessing notions from photonic analogy, we propose a generalization of the existing BOs in photonic Floquet lattices, namely the “photonic Floquet–Bloch oscillations”, which refer to rescaled photonic Bloch oscillations with a period of extended least common multiple of the modulation period and the Bloch oscillation period. Next, we report the first visual observation of such photonic Floquet–Bloch oscillations (FBOs) by employing waveguide fluorescence microscopy. Most significantly, the FBOs surpass the existing BOs in Floquet systems and exhibit exotic properties on their own, including fractal spectrum and fractional Floquet tunneling. This new transport mechanism offers an intriguing method of wave manipulation that may contribute to rapidly developing fields in photonics, condensed matter physics, and quantum physics.

DOI: 10.1038/s41377-024-01419-z

Source: https://www.nature.com/articles/s41377-024-01419-z