Abstract
We present laser trapping-controlled crystal growth of protein, hen egg-white lysozyme (HEWL). A
continuous-wave near-infrared laser beam of 1064 nm is focused at a point 10 μm away from the
generated HEWL crystal. Laser trapping of HEWL liquid-like clusters in solution firstly forms a
millimeter-sized highly concentrated domain, inside which the crystal growth of the specific target
crystal is realized and controlled. At the beginning of the irradiation, the crystal growth rate is extremely
suppressed compared to that in spontaneous crystal growth, while it is enhanced by the continuous
irradiation. The suppress and the enhancement of crystal growth rate can be controlled by changing
laser power and polarization direction. The dynamics and mechanism of this unique crystal growth is
discussed from the viewpoint of large, stable domain formation consisting of the HEWL liquid-like
clusters and by considering the rigidity and anisotropy of the molecules/clusters in the domain.
