多模光纤中的时空波包具有可控制的动态运动和可调节的群体速度
Xinzhou Su1, Kaiheng Zou2, Yingning Wang2
1Department of Electrical and Computer Engineering, Univ. of Southern California, Los Angeles, CA, USA. xinzhous@usc.edu.
Nature communications
|February 27, 2025
概括
研究人员在多模纤维中创建了新的时空波包 (STWPs),使可控制的运动和可调节的组速度成为可能. 这一突破克服了光纤光学领域的先前挑战,为光操纵开辟了新的途径.
科学领域:
- 光学和光子学 在光学和光子学.
- 光纤光学是指光纤的使用.
- 波浪现象是一种波浪现象.
背景情况:
- 时空波包 (STWP) 在自由空间中表现出独特的时空动态.
- 将STWP合到多模纤维是具有挑战性的,因为离散的纤维模式和结构依赖的传播常数.
研究的目的:
- 在分级索引多模纤维中展示具有可控制横向轮运动和可重新配置组速率的STWP.
- 克服合成STWP在光纤中的局限性.
主要方法:
- 通过在频率线和相应的光纤模式之间建立线性关联来合成STWP.
- 使用分级索引多模式纤维进行光传播.
主要成果:
- 经过证明的STWPs具有轴向可控制的横向形状运动和4.8 ps的周期.
- 实现了可重新配置的组速度,可从亚光 (0.870c) 和超光 (1.35c,10c) 调整为负值 (-3.3 × 10^8 m/s).
结论:
- 在多模光纤中成功生成和控制STWP,这是光纤技术的重大进步.
- 调整组速度的能力为光通信和信号处理中的新应用提供了潜力.
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