Size-Selective Optical Printing of Silicon Nanoparticles through Their Dipolar Magnetic Resonance

Surfactant-free silicon nanoparticles of a predefined and narrow (σ < 10 nm) size range can be selectively immobilized on a substrate by optical printing from a polydisperse colloidal suspension. The size selectivity is based on differential optical forces that can be applied on different sized nanoparticles by tuning the light wavelength to their size-dependent magnetic dipolar resonance.