Laser-Induced Alignment of Nanoparticles and Macromolecules for Coherent-Diffractive-Imaging Applications

Laser-induced alignment of particles and molecules was long envisioned to support three-dimensional structure determination using "single-molecule diffraction" with X-ray free-electron lasers [PRL 92, 198102 (2004)]. However, the alignment of isolated macromolecules has not yet been demonstrated also because quantitative modeling is very expensive. We computationally demonstrated that the alignment of nanorods and proteins is possible with a standard laser technology. We performed a comprehensive analysis on the dependence of the degree of alignment on molecular properties and experimental details, e.g., particle temperature and laser-pulse energy. Considering the polarizability anisotropy of about 150,000 proteins, our analysis revealed that most of these proteins can be aligned using realistic experimental parameters.