Related papers: Optonanofluidics: Modelling fluid flow through sur…
The theory for linear deformations of fluid microparticles in a laser beam of Gaussian profile is presented, when the beam focus is at the particle center as in optical trapping. Three different fluid systems are considered: water…
Transformation optics (TO) is a new method to design metamaterials that can manipulate electromagnetic fields. Inspired by the traditional TO techniques which is mostly based on the solid metamaterials with a limited range of tunability, a…
Here we show a folding-stretching instability in a microfluidic flow focusing device using silicon oil (100cSt) and water. The fluid dynamics video demonstrates an oscillating thread of oil focused by two co-flowing streams of water. We…
Most of the vibrating mechanisms of optofluidicsystems are based on local heating of membranes that in-duces liquid flow. We report here a new type of diaphragmpump in a liquid film based on the optical radiation pres-sure force. We…
Thermo-osmotic flow around a microparticle in a liquid is characterized by observing and analyzing the distribution of tiny particles, i.e., tracers, near the microparticle's surface. First, an optical trapping laser is used to localize the…
Deformations of horizontal liquid interfaces by optical radiation pressure are generally expected to display similar behaviors whatever the direction of propagation of the exciting laser beam is. In the present experiment we find this…
The Marangoni effect refers to fluid flow induced by a gradient in surface tension at a fluid-fluid interface. We determine the full three-dimensional Marangoni flow generated by a non-uniform surface tension profile at the interface of a…
Microfluidic techniques have been extensively developed to realize micro-total analysis systems in a small chip. For microanalysis, electro-magnetic forces have generally been utilized for the trapping of objects, but hydrodynamics has been…
It was recently shown theoretically that it is possible to pull a spherical dielectric body towards the source of a laser beam [Nature Photonics {\bf 5}, 531 (2011)], a result with immediate consequences to optical manipulation of small…
The Marangoni contraction of sessile droplets occurs when a binary mixture of volatile liquids is placed on a high-energy surface. Although the surface is wetted completely by the mixture and its components, a quasi-stationary non-vanishing…
Droplet microfluidics combined with optical detection has become a powerful approach for high-throughput single-cell assays, but these systems often face limited sensitivity and signal heterogeneity due to optical and geometrical…
When an evaporating water droplet is deposited on a thermally conductive substrate, the minimum temperature will be at the apex due to evaporative cooling. Consequently, density and surface tension gradients emerge within the droplet and at…
When a drop of a volatile liquid is deposited on a uniformly heated wettable, thermally conducting substrate, one expects to see it spread into a thin film and evaporate. Contrary to this intuition, due to thermal Marangoni contraction the…
Droplets are natural candidates for use as microfluidic reactors, if active control of their formation and transport can be achieved. We show here that localized heating from a laser can block the motion of a water-oil interface, acting as…
In this fluid dynamics video, results from high fidelity numerical simulations are presented, which have been carried out to study the flow and droplet dynamics of liquid sheets formed by two impinging jets. A three-dimensional…
We have investigated the bleaching dynamics that occur in optofluidic dye lasers where the liquid laser dye in a microfluidic channel is locally bleached due to optical pumping. We find that for microfluidic devices, the dye bleaching may…
A novel method to pump fluid in lab on chip devices with velocities up to tens of micrometer per second is introduced. A focused laser beam locally heats up an electrolyte. A net charge tends to accumulate in the heat-absorbing area, due to…
In this paper, we provide the semi-analytical solution of the temperature and flow fields of a fluid confined in a narrow space between two parallel plates. The temperature increase is triggered by photothermal effects of fluids and/or…
We study numerically the deformation of sessile dielectric drops immersed in a second fluid when submitted to the optical radiation pressure of a continuous Gaussian laser wave. Both drop stretching and drop squeezing are investigated at…
We propose a novel microfluidic "opposed-flow" geometry in which the continuous fluid phase is fed into a junction in a direction opposite the dispersed phase. This pulls out the dispersed phase into a micron-sized jet, which decays into…