Crystals of glycine grow immediately when hit by a laser at the edge of a droplet, but they actually start to dissolve at the center.
Optical trapping with lasers creates a starkly different reaction in matter based on its position within a liquid. This experiment showed that crystal growth is drastically enhanced at the air-solution interface while the opposite happens just millimeters away. Most scientists assumed that a laser's energy would have a uniform effect on a small volume of liquid. This research reveals that the surface of a droplet is a unique environment where light and matter interact in counterintuitive ways. Understanding this 'edge effect' will allow pharmaceutical companies to grow more uniform crystals for drugs with much higher precision. It reveals a hidden power of surfaces in controlling the assembly of matter.
Optical Trapping-Enhanced Glycine Crystal Growth Achieved near Air–Solution Interfaces
SSRN · 6721625
Controlling crystal growth in solution is essential for fabricating crystalline materials with tailored sizes and morphologies. Here, we investigate the influence of the air–solution interface on optical trapping-enhanced crystal growth using glycine as a model system. The growth response of glycine crystals was found to strongly depend on their position within a solution droplet under focused trapping laser irradiation. At the droplet center, crystals initially dissolved and subsequently transi