Finite-difference time-domain analysis of photonic nanojets from liquid-crystal-containing microcylinder

Abstract

The photonic nanojet (PNJ) from a microcylinder with liquid crystals (LCs) showing tangential molecular alignment inside the microcylinder has been numerically analyzed on the basis of the finite-difference time-domain method. By introducing a small degree of birefringence, the characteristics of the PNJ, such as propagation length and polarization state, can be drastically changed. The azimuth angle and the ellipticity of the elliptically polarized PNJ obtained from the LC microcylinder changes within the propagation lengths in the micrometer range even in the isotropic matrix, which might be attributed to the jet like spatial profile of the PNJ. By using LC microcylinders or microspheres, we may obtain a rich variety of PNJs with unique polarization characteristics, which might open a new avenue for the development of novel optical devices with electrical tunability.

FDTD analysis of photonic nanojet from self-organized liquid crystal microsystems

“…We have numerically analyzed the generation of a PNJ from a microcylinder with LCs showing radial hedgehog and tangential molecular alignments on the basis of the finite-difference time-domain (FDTD) method. 15) Here we show that the PNJ from the LC microcylinder shows unique optical characteristics reflecting their birefringence. Our findings may open the way for the development of novel optical devices.…”

All-dielectric concentration of electromagnetic fields at the nanoscale: the role of photonic nanojets

“…LCs have been extensively utilized in many elds including organic electronics and energy conversion, the creation of nanostructured materials or ordering nano-and microparticles, actuators, polymer-dispersed LCs, and spatial light modulators. [69][70][71][72][73] Liu et al, 74 Matsui et al, 75 Eti et al, 76 and Du et al, 77 have investigated the properties of PNJs as functions of the phase transitions of LCs, but the rst experimental imaging of tunable PNJs using LC control appears to have been achieved by Matsui and Tsukuda. 78 In their experiments, a LC microdroplet formed in a polydimethylsiloxane (PDMS) matrix is sandwiched between indium-tin-oxide (ITO) electrodes.…”

Switchable Photonic Nanojet by Electro-Switching Nematic Liquid Crystals

“…Thus, tuning the refractive index of the background medium by external stimuli becomes a key to manipulating PNJ dynamically. Recently, various kinds of micron-sized optical functional materials and devices using liquid crystal (LC) microdroplets have been proposed [28,29,30,31,32]. Primarily, the generation of a PNJ from an LC microcylinder with tangential molecular alignment was theoretically analyzed by finite-difference time-domain (FDTD) [28].…”