Quantitative Characterization of Photonic Sail Candidates using Nanocantilever Displacement

Author: Joseph E. Meany, Ph.D.

Background: Demonstrations of photonically-propelled materials for solar and laser sailing have relied on indirect techniques for determining the propulsion efficiency. These methods, utilizing drop towers or cameras to determine differential displacement, are necessarily low-throughput and cannot be easily compared directly.  Furthermore, the methods require sample sizes that are prohibitive to the fabrication of low TRL photonic materials (e.g. thin-film metasurfaces) that discourages rapid iterative testing. Herein, a nanocantilever-based test bed is proposed to simplify and standardize the determination of the characteristic acceleration for a given sail swatch. The proposed system is designed to allow for flexible, automated spectral analysis, requiring sample sizes ~10 µm2. This system is scalable to the micro- and macroscale as material technologies mature and advance toward deployment scale. 

Objective: Outline the physical principles underlying a nanocantilever detection system to support small-area swatches of candidate photonic sail materials. 

Methods: Classical physics modelling to support the basic feasibility of the approach.