Capillarity-driven assembly of colloidal microbullets at an air/water interface

The pronounced asymmetric interface distortion around microbullets leads to a strong capillary attraction. This attraction is dependent on orientation and results in preferred lateral particle interactions. A series of laterally aligned microbullets form smectic-like domains that subsequently attract each other, resulting in the development of a rigid gel-like monolayer. The arrangement of this monolayer strongly resembles a smectic-like order at short distances, while exhibiting disorder attributed to different domain orientations at larger distances.