Nanoscale Optical Trapping: A Review

Abstract Optical trapping is the craft of manipulating objects with light. Decades after its first inception in 1970, the technique has become a powerful tool for ultracold‐atom physics and manipulation of micron‐sized particles. Yet, optical trapping of objects at the intermediate—nanoscale—range is still beyond full grasp. This matters because the nanometric realm is where several promising advances, from mastering single‐molecule experiments in biology, to fabricating hybrid devices for nanoelectronics and photonics, as well as testing fundamental quantum phenomena in optomechanics, are anticipated to produce impactful breakthroughs. After a comprehensive, theoretical introduction to the phenomenon of optical trapping, this review delves into assessing the current state‐of‐the‐art for optical manipulation of objects at the nanoscale. Emphasis is put on presenting the challenges that coalesced into driving the field to its current development, as well as discussing the outstanding barriers, which might lead to future advancements in the field.