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通过旋转轨道相互作用在分数轨道角动量束中的旋转角动量调制

Xusheng Chen¹, Fanfei Meng², Kang Du³

¹Nanophotonics Research Centre, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen, 518060, China.

Nanophotonics (Berlin, Germany)

|December 17, 2025

概括

分数轨道角动量 (FOAM) 束通过将拓电荷扩展到整数之外,使自旋角动量 (SAM) 的连续控制成为可能. 旋转轨道相互作用操纵的这一突破为结构光应用开辟了新的途径.

科学领域:

* 量子光学和光子学.
* 结构化的光场生成和操纵.

背景情况:

* 旋转角动量 (SAM) 和轨道角动量 (OAM) 在近轴场中是独立的,但通过旋转轨道相互作用 (SOI) 在受限场中是合的.
* 具有整数拓电荷 (TC) 的传统OAM光束导致离散的SAM状态,阻碍了连续的SAM控制.
*SOI允许创建具有拓特征的结构光,如光学 skyrmions.

研究的目的:

* 探索分数轨道角动量 (FOAM) 束,以实现对SAM的连续和精确控制.
* 为了建立FOAM的分数有效TC和SAM矢量方向分布之间的直接数学关系.
*通过实验验证理论预测,并展示FOAM TCs的新型反向检测方法.

主要方法:

* 理论推导FOAM分数有效TC和SAM矢量方向之间的关系.
* 实验验证使用定制的近场测绘系统来测绘SAM分布.
* 开发一种反向检测方法来测量FOAM分数有效TCs.

主要成果:

* 证明了FOAM分数有效TC和SAM矢量方向之间的直接数学联系.
*实验地绘制了由FOAM光束调节的不同的SAM分布.
* 在使用反向检测方法测量FOAM分数有效TC时获得了高精度 (10−5理论,10−2实验).

结论:

*FOAM光束为SAM的连续和精确控制提供了一条途径,克服了离散TC的局限性.
*这项研究增强了对光物质相互作用中的SOI机制的基本理解.
*潜在的应用包括先进的光场操纵,光通信和新型光子设备.

关键词:

分数轨道的角运动量.旋转角运动量旋转角运动量旋轨道相互作用

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