Observation of Anthracene Crystallization under Irradiation of Terahertz Free-Electron Laser

We explore the potential of using terahertz (THz) free-electron laser (FEL) to induce crystal nucleation in organic materials. We observe the crystallization process of anthracene triggered by irradiating THz-FEL pulses into the supersaturated solution. We found that repeated irradiation with THz-FEL led to the formation of cavitation bubbles near the focal point, which caused many anthracene crystals to nucleate simultaneously. This is the first demonstration of THz-FEL-induced crystallization.