Figure 5: Quantitative analysis of 3D optical force fields.
From: Helicity-dependent three-dimensional optical trapping of chiral microparticles
(a,b) Spatial distribution of the magnitude (colour map) and orientation (vector plot) of the calculated optical force exerted on a droplet located around the origin, namely −3R<z<3R and −3R<r<3R, for {l=0, Λχ=+1, w1/R=2/3} and {l=1, Λχ=−1, w1/R=1}, with θ0=5° and w1=20 μm. (c,d) Experimental data for the longitudinal component of the force along the z axis, Fz(0, z). (e,f) Experimental data for the transverse component of the force along the axis r that passes through the origin, Fr(r, 0). Experimental conditions: the experimental data set (dot markers) corresponds to 40 independent realizations, whose standard deviation range is indicated by solid curves, whereas dashed curves are the results of simulations without adjustable parameters. Left panels correspond to P≈20 mW and R=29 μm, whereas right panels refer to P≈70 mW and R=20 μm. The constant drag velocity for radial force measurements is V0=36 μm s−1, see text for details.
