Zhang Zhen, Li Yuan, Sun Xiankai, Shu Xuewen
Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, China.
Department of Electronic Engineering, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China.
Light Sci Appl. 2024 Apr 28;13(1):99. doi: 10.1038/s41377-024-01419-z.
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.
布洛赫振荡（BOs）是一种重要的输运现象，在静态系统中已得到广泛研究，但在弗洛凯系统中仍然神秘莫测。在此，通过利用光子类比的概念，我们提出了光子弗洛凯晶格中现有布洛赫振荡的一种推广形式，即“光子弗洛凯 - 布洛赫振荡”，它指的是调制周期和布洛赫振荡周期的扩展最小公倍数周期的重新标度的光子布洛赫振荡。接下来，我们通过使用波导荧光显微镜首次直观观察到了这种光子弗洛凯 - 布洛赫振荡（FBOs）。最显著的是，FBOs超越了弗洛凯系统中现有的BOs，并展现出其自身的奇异特性，包括分形谱和分数弗洛凯隧穿。这种新的输运机制提供了一种有趣的波操控方法，可能有助于光子学、凝聚态物理和量子物理等快速发展的领域。
