Fig. 1: Janus particles and the nanofiber-based manipulation concept.
From: Evanescent field trapping and propulsion of Janus particles along optical nanofibers
a, b Scanning electron microscope (SEM) images of silica-gold JPs used in this study (d = 10 nm and 20 nm is the gold coating thickness). c Artistic view of a JP in contact with the waist region of an ONF guiding a fundamental mode, HE11, polarized in the symmetry plane of the ONF-JP system (yz-plane). The electric field distribution (same as in Fig. 2e) is simulated for the wavelength of 1.064 μm, 0.7-μm-thick ONF, 3-μm particle, 20-nm-thick gold cap tilted forward at an angle α = 30∘ with respect to y. The particle is propelled along z by the scattering optical force, while staying trapped in the y direction due to the attractive gradient force.
