Trapping of dielectric particles with light-induced space-charge fields

Abstract

Light-induced space-charge fields in lithium niobate crystals are used to trap and manipulate dielectric particles on the surface of such crystals. Without any external voltage source, strong field gradients are present in the proximity of the crystal surface. These are used to trap particles with diameters in the range between 100 nm and some tens of micrometers.

Recent Achievements on Photovoltaic Optoelectronic Tweezers Based on Lithium Niobate

“…First experiments demonstrated the manipulation of dielectric and metallic micro-and nanoparticles using x-or y-cut lithium niobate crystals, i.e., substrates with the polar axis parallel to the surface [17,34]. The work was soon extended to 2D particle patterns still using x-or y-cuts.…”

“…The first works on PVT reported their ability to trap and pattern micrometric particle [33,34] and it is in this subject where the field has reached a greater maturity. First experiments demonstrated the manipulation of dielectric and metallic micro-and nanoparticles using x-or y-cut lithium niobate crystals, i.e., substrates with the polar axis parallel to the surface [17,34].…”

Pyroelectric Trapping and Arrangement of Nanoparticles in Lithium Niobate Opposite Domain Structures

“…However, for a number of applications massive simultaneous particle manipulation is required. In this case the use of light [4][5][6] or thermally-induced 7 electric fields generated in certain ferroelectrics have been recently proposed and successfully applied. However, these techniques are still young and new developments and applications are continuously arising 8,9 .…”

Optofluidic applications with lithium niobate nanowires

“…The photovoltaic effect from bulk LiNbO 3 , generating an electrical dipole has for instance been used for the dielectrophoretic trapping of particles 1 . Similarly the piezoelectric effect was utilized for dieletrophoretic trapping of microparticles 2 .…”