Plasmonic Nanostructures on Tips of Tapered Optical Fibers for Large EM Enhancement

In this paper, we employ finite difference time domain (FDTD) simulations to show that plasmonic nanoantenna structures present on tips of tapered optical fibers have significantly greater electromagnetic field (EM) enhancements as compared with non-tapered optical fibers having the plasmonic nanoantennas on their tips. Moreover, we compare the EM enhancement of several plasmonic nanoantenna structures present on tapered as well as nontapered optical fiber tips. Symmetrical structures such as crossed nanoantennas were designed and simulated as these structures are less polarization dependent.