This article investigates the stability of 'laser sail'-style spacecraft constructed from dielectric metasurfaces with areal densities <1g/m 2 . We show that the microscopic optical forces exerted on a metasurface by a high power laser (100 GW) can be engineered to achieve passive self-stabilization, such that it is optically trapped inside the drive beam, and self-corrects against angular and lateral perturbations. The metasurfaces we study consist of a patchwork of beam-steering elements that reflect light at different angles and efficiencies. These properties are varied for each element across the area of the metasurface, and we use optical force modeling tools to explore the behavior of several metasurfaces with different scattering properties as they interact with beams that have different intensity profiles. Finally, we use full-wave numerical simulation tools to extract the actual optical forces that would be imparted on Si/SiO2 metasurfaces consisting of more than 400 elements, and we compare those results to our analytical models. We find that under first-order approximations, there are certain metasurface designs that can propel 'laser-sail'-type spacecraft in a stable manner.

Graphene plasmonic resonators have been broadly studied in the terahertz and mid-infrared ranges because of their electrical tunability and large confinement factors, which can enable the dramatic enhancement of light–matter interactions. In this work, we demonstrate that the characteristic scaling laws of resonant graphene plasmons change for smaller (<40 nm) plasmonic wavelengths and that those changes modify the optical confinement properties of graphene plasmonic resonators, allowing their operational frequency to be expanded into the short-wave infrared (SWIR). These effects are realized in centimeter-scale arrays of graphene resonators as narrow as 12 nm, which are created using a novel, bottom-up block copolymer lithography method. Measurements of these structures reveal that their plasmonic resonances are strongly influenced by nonlocal and quantum effects, which push their resonant frequency well into the SWIR (free-space wavelength ∼2.2 μm), 75% higher frequency than previous experimental works. The confinement factors of these resonators reach 137 ± 25, among the largest reported in literature for any type of 2D optical resonator. The combined SWIR response and large confinement of these structures make them an attractive platform to explore ultrastrongly enhanced spontaneous emission.

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Patterning graphene into nanostructures enables the coupling of free space radiation to plasmons in graphene. Here, we demonstrate block copolymer based fabrication can create sub 20 nm nanostructures in a scalable, efficient, and repeatable manner.

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