Abstract
In this paper, we propose and numerically simulate a novel optical trapping process based on the enhancement and the confinement of both magnetic and electric near-fields by using gold Diabolo Antenna (DA). The later was recently proposed to generate huge magnetic near-field when illuminated by linearly polarized wave along its axis. Numerical 3D – FDTD simulation results demonstrate the high confinement of the electromagnetic field in the vicinity of the DA. This enhancement is then exploited for the trapping of nano-particles (NP) as small as 30 nm radius. Results show that the trapping process greatly depends on the particle dimensions and that three different regimes of, trapping at contact, trapping without contact, or pushing can be achieved within the same DA. This doubly resonant structure opens the way to the design of a novel generation of efficient optical nano-tweezers that allow manipulation of nano-particles by simply changing the operation wavelength.
Highlights
In this paper, we propose and numerically simulate a novel optical trapping process based on the enhancement and the confinement of both magnetic and electric near-fields by using gold Diabolo Antenna (DA)
3D trapping with such beams is a very hard task due to the radiation pressure in the longitudinal direction that tends to push the particles along the light propagation direction
It results from extensive Finite Difference Time Domain (FDTD19)-based numerical simulations that were conducted in order to optimize the enhancement of both magnetic and electric near-fields[11]
Summary
We propose and numerically simulate a novel optical trapping process based on the enhancement and the confinement of both magnetic and electric near-fields by using gold Diabolo Antenna (DA). This enhancement is exploited for the trapping of nano-particles (NP) as small as 30 nm radius. In 2011, a review paper by Juan et al.[14] discusses several of such plasmonic structures in the context of optical trapping In all these cases, the electric field confinement, induced by the nano-antenna resonance, is at the origin of the force enhancement and non-resonant particles are usually considered to insure a weak coupling with the NA and a small modification of the resonant mode distribution. It results from extensive Finite Difference Time Domain (FDTD19)-based numerical simulations (homemade code) that were conducted in order to optimize (see the Methods section) the enhancement of both magnetic and electric near-fields[11]. The latter case is more appropriate in common optical trapping experiments due to the particle weight compensation by the buoyancy
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
