Selective transmittance of linearly polarized light in thin films rationally designed by FDTD and FDFD theories and fabricated by glancing angle deposition

Abstract

Columnar thin films exhibiting linear polarization selectivity have been theoretically investigated and fabricated using the glancing angle deposition (GLAD) technique. The film structure employed an s-shaped columnar morphology that may be either smoothly bent or composed of discrete segments. Finite-difference time-domain and frequency-domain methods have been used to model these thin film structures numerically. Simulation results have yielded optimal geometries in which the films exhibit either a single frequency band with polarization-selective transmittance or two separated frequency bands each transmitting one of two orthogonal linearly polarized modes. Based on these designs, a series of TiO2 films were grown by GLAD with continuous and discrete s-shaped columnar morphology. Experimental measurements by spectrophotometry verified the presence of selectivity for the orthogonal linearly polarized modes. Films with more then 24 periods were found to have polarization selectivity approaching unity. The agreement between the simulation and experimental results demonstrates the potential for future theoretical development of highly selective polarization filters based on GLAD thin films.

Optical properties of nanostructured WO3 thin films by GLancing Angle Deposition: Comparison between experiment and simulation

“…In 2008, Leontyev et al [26] used a Finite-Difference Time-Domain (FDTD) code to study the transmission properties of nanostructured thin films produced by GLAD. They showed that it was possible to tune selective transmission of linearly polarized light for thin films with S-shape structures nano-designed by GLAD.…”

Optofluidic Modulation of Self-Associated Nanostructural Units Forming Planar Bragg Microcavities

“…14,15 In the called "sculptured thin films", 16,17 a class of nanostructured GLAD materials, their singular topography, geometry and in-depth architecture permits an effective control of their refractive index and birefringence and the development of optically active photonic structures [18][19][20][21][22][23] or helicoidally bi-anisotropic media acting for example as narrow band pass optical filters, 24 selective circularly polarized light transmitters 25 or selective linearly polarized transmitters. 26 In this regard, although polarization inactive SiO 2 -TiO 2 one dimensional photonic crystals (1DPC) 27,28 and Bragg microcavities (BM) 29 have been also prepared by PVD-OAD, no polarization activity is known for such two-oxide layered systems.…”

Nanoindentation and scratch resistance of multilayered TiO2-SiO2coatings with different nanocolumnar structures deposited by PV-OAD

“…In our group, TiO 2 -SiO 2 multilayer nanocolumnar systems behaving as 1D photonic crystals or Bragg microcavities have been used for liquid sensing applications [6,7]. Applications as polarized light emitters, selective transmitters or humidity sensors have been reported by others [8,9,10]. However, mechanical properties such as hardness, elastic modulus or interfacial cohesion of this type of nanostructured multilayer TiO 2 -SiO 2 coatings have not been reported so far.…”