Optical manipulation of microparticles and cells on silicon nitride waveguides

Abstract

We demonstrate the optical manipulation of cells and dielectric particles on the surface of silicon nitride waveguides. Glass particles with 2microm diameter are propelled at velocities of 15microm/s with a guided power of 20mW. This is approximately 20 times more efficient than previously reported, and permits to use this device on low refractive index objects such as cells. Red blood cells and yeast cells can be trapped on the waveguide and pushed along it by the action of optical forces. This kind of system can easily be combined with various integrated optical structures and opens the way to the development of new microsystems for cell sorting applications.

Giant resonant light forces in microspherical photonics

“…After that, we present our experimental observations of propelling of polystyrene microspheres in the near-field vicinity of tapered microfibers immersed in water. For a certain small fraction of spheres with D<15-20 mm, we observed giant power normalized propelling velocities ,10 mm s 21 W 21 that exceed the previous measurements in various evanescent couplers [20][21][22][23][24][25] by more than an order of magnitude. These extraordinary high propelling efficiencies approach estimations made in a total absorption limit that indicates that a significant part of the total guided power is used for the creating light pressure.…”

“…The propelling of dielectric microspheres was studied in liquid-immersed evanescent couplers based on dielectric waveguides, [20][21][22][23] tapered fibers 24 and prisms. 25 The light pressure in such structures and devices is determined by the conservation of the total momentum along the propagation direction.…”

“…The propelling velocity normalized by the incident power has been found to be below ,1 mm s 21 W 21 for dielectric microspheres with diameters (D) from 2 to 20 mm. [20][21][22][23][24][25] Propelling efficiencies can be increased for strongly absorbing particles. 26 However, in the later case, the dominant mechanism of propelling has been attributed to the photophoretic forces occurring due to non-uniform heating of the light-absorbing particle.…”

Optical Effects Induced by Bloch Surface Waves in One-Dimensional Photonic Crystals

“…However, an electromagnetic gradient can be created not only in the waist region of focused laser radiation. The possibility of trapping and moving nanoparticles and microparticles using an evanescent field that appeared with total internal reflection from a smooth surface and in optical waveguides was shown [64][65][66][67]. Large values of optical field gradients can be achieved by using optical resonances of surface plasmons on metallic films and in plasmonic structures [68][69][70][71][72][73].…”

Long‐distance laser propulsion and deformation‐ monitoring of cells in optofluidic photonic crystal fiber

“…There have also been several reports of optical propulsion of cells along waveguides. For instance, the evanescent edging field of a single guided optical mode has been used to propel particles over distances up to 0.1 mm on planar waveguides [21,22]. This approach has the disadvantage that the transverse optical field decays exponentially from the surface, causing cells to be guided very close to the waveguide surface, resulting in strong adhesion forces.…”