Banerjee Ritwik, Maiti Tanmoy
Plasmonics and Perovskites Laboratory, Indian Institute of Technology Kanpur UP 208016 India
Nanoscale Adv. 2024 Sep 10;6(23):5960-70. doi: 10.1039/d4na00336e.
Optical vortices have a topologically charged phase singularity and zero intensity distribution in the centre. Optical vortex creation is regarded as a significant means for information transmission for applications in quantum computing, encryption, optical communication, In this study, using finite-difference time-domain (FDTD) simulation, we calculated the electric field intensity and phase distribution of 2D lattices of optical vortices generated from various polygonal plasmonic lens structures using surface states of a Weyl semimetal (MoTe). It was shown that a hexagonal lens is the best performing plasmonic lens. Further, we posited here a unified mathematical formulation for optical electrical field and phase distribution in the near field for any polygonal plasmonic lens. Our theoretical calculation corroborated well with FDTD results, validating the proposed generalized formula. Such plasmonic lens structures demonstrating scaling behavior offer great potential for designing next-generation optical memories.
光学涡旋具有拓扑电荷相位奇点且中心强度分布为零。光学涡旋的产生被视为量子计算、加密、光通信等应用中信息传输的重要手段。在本研究中，我们使用时域有限差分（FDTD）模拟，计算了利用外尔半金属（MoTe）的表面态从各种多边形等离子体透镜结构产生的二维光学涡旋晶格的电场强度和相位分布。结果表明，六边形透镜是性能最佳的等离子体透镜。此外，我们在此提出了一个适用于任何多边形等离子体透镜近场中光电场和相位分布的统一数学公式。我们的理论计算与FDTD结果吻合良好，验证了所提出的广义公式。这种表现出缩放行为的等离子体透镜结构为设计下一代光学存储器提供了巨大潜力。
