Photonic band in two-dimensional lattices of micrometer-sized spheres mechanically arranged under a scanning electron microscope

Abstract

Two-dimensional photonic crystals of dielectric spheres with a 2.1 μm diameter have been fabricated by arranging individual spheres using a micromanipulation technique in a scanning electron microscope. A buildup of photonic bands from whispering gallery modes has been observed as the number of spheres increased, by measuring the transmission spectra for lattices composed of various numbers of spheres. The photonic band dispersion curves were experimentally obtained for a finite system made of 91 spheres from the transmission spectra for oblique incidence in the near-infrared region. They were in good agreement with the results of a numerical calculation for an infinite lattice. Since this mechanical manipulation technique enables us to control the arrangement of individual optical wavelength-sized scatterers, it provides a new way to systematically investigate various photonic band effects.

Modification of emission of CdTe nanocrystals by the local field of Langmuir–Blodgett colloidal photonic crystals

“…Such a PBG was calculated using the whispering gallery mode-coupling model. 21 This model explains reasonably well the observed far-field transmission spectra and their angular dependence. Moreover, this theory predicts considerable broadening of the minima bandwidth due to light leakage to the substrate.…”

“…19 Colloidal PhCs can be directly deposited on the surface of the light emitting film using the well-controllable LangmuirBlodgett ͑LB͒ technique. 20 When compared to micromanipulation 21 or colloidal self-assembly, 19 the LB method offers large area coatings and precision in terms of depositing the required number of monolayers of spheres.…”

( 2 + 1 ) -dimensional photonic crystals from Langmuir-Blodgett colloidal multilayers

“…One approach is based on consideration of 2D PhC, the PBG of which is calculated by coupling of whispering gallery mode resonances of individual spheres in the 2D crystal. 10 The lowest wavelength resonance in this model appears at D / Ϸ 0.9, which corresponds to the 545 nm minimum in our case ͑Fig. 1͒.…”

“…Moreover, no spectroscopic evidence has been demonstrated to prove the formation of a 3D lattice in LB multilayers. 9 On the other hand, optical spectra of 2D hexagonal sphere crystals were studied only at wavelengths shorter than the sphere diameter, 10,11 i.e., in the range of their 2D PBG.…”

Understanding of transmission in the range of high-order photonic bands in thin opal film

“…8,9 These minima were associated with excitation of optical eigenmodes of 2D PhC, which propagate in plane of a monolayer. The aim of this work is to demonstrate that similar effect can be observed in thin opal films.…”