Theoretical analysis for the optical deformation of emulsion droplets

Abstract

The frequent occurrence of hard X-ray emission from the top of Ñaring loops was one of the discoveries by the Hard X-Ray Telescope on board the Japanese Y ohkoh satellite. In this paper we take a Ñare current-sheet geometry and show how the combined e †ect of magnetic Ðeld convergence and pitchangle scattering of nonthermal electrons injected at the top of the loop results in the generation of a looptop source with properties akin to those observed by Y ohkoh. We demonstrate that a looptop source can be produced in both impulsive and gradual phase loops. We further present a possible mechanism for the generation of high-temperature "" ridges ÏÏ in the loop legs.

Stability and interaction forces of oil-in-water emulsions as observed by optical tweezers – a proof-of-concept study

“…Measurements on so deformable spheres such as emulsion droplets involves that the droplets are deformed when residing in the optical trap, as described in recent studies. [58][59][60] The absolute surface distance between two emulsion droplets trapped in the optical tweezers is therefore not clearly dened. The absolute trap distance is known and the droplet size for the trapped droplets in each measurement series is measured manually.…”

Optical trapping of interfaces at ultra-low interfacial tension

“…3,[8][9][10] Near-critical phase separated microemulsions have an ultra-low interfacial tension as well, which was exploited to study the effect of thermal uctuations on droplet snap-off. [20][21][22] In order to do similar experiments on droplets or interfaces in colloidal systems, one would need to manipulate multiple particles simultaneously. Recently, several non-contact methods were developed to study interface properties by actively deforming systems like polymer and surfactant solutions, and (phase separated) molecular uids.…”

Radiation-pressure-induced nonlinearity in microdroplets

“…Theoretical description of the droplet shape dynamics were developed in the aforementioned work to quantify the effect of radiation pressure on the drop interface. In a recent work [28], large droplet deformation under optical pressure was also predicted numerically when low interfacial tension was assumed (∼ 1 × 10 −6 N/m).…”