https://advances.sciencemag.org/content/7/7/eabe1127
Controlled levitation of nanostructured thin films for sun-powered near-space flight View ORCID ProfileMohsen Azadi1, View ORCID ProfileGeorge A. Popov2, Zhipeng Lu3, View ORCID ProfileAndy G. Eskenazi2, View ORCID ProfileAvery Ji Won Bang1, View ORCID ProfileMatthew F. Campbell1, View ORCID ProfileHoward Hu1 and View ORCID ProfileIgor Bargatin1,* See all authors and affiliations Science Advances 12 Feb 2021: Vol. 7, no. 7, eabe1127 DOI: 10.1126/sciadv.abe1127 Article Figures & Data Info & Metrics eLetters PDF Abstract We report light-driven levitation of macroscopic polymer films with nanostructured surface as candidates for long-duration near-space flight. We levitated centimeter-scale disks made of commercial 0.5-micron-thick mylar film coated with carbon nanotubes on one side. When illuminated with light intensity comparable to natural sunlight, the polymer disk heats up and interacts with incident gas molecules differently on the top and bottom sides, producing a net recoil force. We observed the levitation of 6-mm-diameter disks in a vacuum chamber at pressures between 10 and 30 Pa. Moreover, we controlled the flight of the disks using a shaped light field that optically trapped the levitating disks. Our experimentally validated theoretical model predicts that the lift forces can be many times the weight of the films, allowing payloads of up to 10 milligrams for sunlight-powered low-cost microflyers at altitudes of 50 to 100 km. -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/CAJ3C-04BSwPhc9Wbz2Lc1wV9rUAXM2GbVrPKSnh3tTrndw9PxA%40mail.gmail.com.
