Collaborative research between the lab of Mark Sadgrove (Tokyo University of Science) and Hiromi Okamoto (Institute for Molecular Science). In this work, the authors show that an emitter coupled to a metallic nanorod can produce optical excitations with a significant and controllable spin component. To achieve the necessary ~10 nm resolution to demonstrate the effect, a tightly focussed beam of electrons was employed, exciting plasmonic modes within the rod at a well-defined point. While this method does not typically allow the measurement of near-field optical spin, here, the authors placed the rod on an optical nanofiber, which supports the “chiral coupling”. By measuring the imbalance in the intensity output at the fiber ends, the net spin of the created plasmonic mode could be read out.
This research was published online in Nano Letters on February 9, 2026.

https://pubs.acs.org/doi/10.1021/acs.nanolett.5c05644