2026-04-24 東京理科大学,分子科学研究所
図: ナノ光ファイバー上のナノ粒子のエバネッセント光による輸送実験。
（左）ファイバーの片側から円偏光を入射した場合のナノ粒子の位置と速度の変化。
（右）ファイバーの両側から直線偏光と円偏光を入射した場合のナノ粒子の位置と速度の変化。
＜関連情報＞
- https://www.tus.ac.jp/today/archive/20260424_1873.html
- https://www.nature.com/articles/s41467-026-71585-8
ナノファイバーのエバネッセント場におけるナノ粒子のキラリティ選択的光輸送 Chirality-selective optical transport of nanoparticles in the evanescent field of a nanofibre
Georgiy Tkachenko,Akiyoshi Suda,Hyo-Yong Ahn,Yamato Iida,Ichiro Kurihara,Koki Saito,In Han Ha,Yining Xuan,Ki Tae Nam,Hiromi Okamoto & Mark Sadgrove
Nature Communications Published:16 April 2026
DOI:https://doi.org/10.1038/s41467-026-71585-8
Abstract
Selective optical manipulation of nanoparticles according to their chirality is a challenge due to the relatively small size of the chirality-dependent optical force. Here, we introduce the evanescent field of optical nanofibres as a promising tool for such manipulation. Using circularly polarised fibre modes, we demonstrate strongly chirality-selective optical transport of a chiral nanoparticle. Our experiments, backed by simulations, show that right- and left-handed circularly polarised modes produce clearly distinct velocities of optically trapped chiral nanoparticles along the nanofibre. Furthermore, using a counterpropagating mode configuration, the non-chiral component of the optical force can be cancelled, yielding selective forward and backward transport. The chiral optical force was found to be significant even for particle ensembles with natural variations in size and form, implementing optical separation of chiral enantiomers at the scale of 100 nm. Further development towards waveguide-assisted enantioselective manipulation approaching the molecular scale can be envisaged.
