English
Related papers

Related papers: Filamentary, my dear Watson

200 papers

Experimentation with obliquely incident light established that all four circular reflectances of a chiral sculptured thin film backed by a metallic mirror contain strong evidence of the circular Bragg phenomenon. When the mirror is removed,…

A stepwise chirping of the periodicity of a chiral sculptured thin film is shown to considerably enhance the bandwidth of the Bragg regime, thereby extending the frequency range of operation as a circular{polarization filter.

Optics · Physics 2020-09-04 Akhlesh Lakhtakia

Axially excited chiral sculptured thin films (STFs) are shown to exhibit the circular Bragg phenomenon in the pre-resonant (long-wavelength) regime but not in some parts of the post-resonant (short-wavelength) regime. Chiral STFs act as…

Optics · Physics 2019-11-19 Akhlesh Lakhtakia. Jason T. Moyer

Theory shows that a slab of a dielectric structurally chiral material (DSCM) exhibits both linear and circular dichroisms because of its anisotropy and structural chirality, for normal as well as oblique incidence. This conclusion was…

Optics · Physics 2018-06-11 Patrick D. McAtee , Akhlesh Lakhtakia

The optical response of gyrotropic and non-gyrotropic dielectric polygonal chiral thin films were investigated using transfer matrix method. The influence of gyrotropy factor, porosity and incident angle of light on Bragg regimes, selective…

Optics · Physics 2019-04-23 F Babaei

The optical rotation and selective transmission spectrum of ambichiral sculptured thin films using transfer matrix method have been calculated. The results of optical modeling showed that optical characteristics ambichiral sculptured thin…

Optics · Physics 2013-12-31 Ferydon Babaei

Setting up an empirical model of optical sensing to exploit the circular Bragg phenomenon displayed by chiral sculptured thin films (CSTFs), we considered a CSTF with and without a central twist defect of $\pi/2$ radians. The circular Bragg…

Optics · Physics 2010-04-13 Tom G. Mackay , Akhlesh Lakhtakia

The concept of local homogenization is invoked in the visible and the sub-visible frequency regimes to estimate the permittivity dyadics of a thin-film helicoidal bianisotropic mediums (TFHBMs)~---~a canonical class of sculptured thin films…

Optics · Physics 2019-10-01 Akhlesh Lakhtakia

The durations and average speeds of ultrashort optical pulses transmitted through chiral sculptured thin films (STFs) were calculated using a finite-difference time-domain algorithm. Chiral STFs are a class of nanoengineered materials whose…

Optics · Physics 2007-12-07 J. B. Geddes , A. Lakhtakia

The generalized ellipsometry formalism is used for a right handed ambichiral sculptured thin film.The amplitude ratios and phase differences of this structure are extracted from the amplitude transmission ratios. The results showed that the…

Optics · Physics 2013-12-31 F Babaei

Being an assembly of identical upright helixes, a chiral sculptured thin film (CSTF) exhibits the circular Bragg phenomenon and can therefore be used as a circular- polarization filter in a spectral regime called the circular Bragg regime.…

Optics · Physics 2019-01-21 Vikas Vepachedu , Akhlesh Lakhtakia

Sculptured thin films (STFs) are nano-engineered materials whose columnar morphology is tailored to elicit desired optical responses upon excitation. Two canonical forms of STFs have been identified. Linear constitutive relations for…

Materials Science · Physics 2010-07-13 Akhlesh Lakhtakia

Many objects in nature and industry are wrapped in a thin sheet to enhance their chemical, mechanical, or optical properties. There are similarly a variety of methods for wrapping, from pressing a film onto a hard substrate, to using…

Soft Condensed Matter · Physics 2019-04-30 Joseph D. Paulsen

The transmission and reflection spectra from a right-handed chiral sculptured zirconia thin film are calculated using the coupled wave theory and the Bruggeman homogenization formalism in conjunction with the experimental data for the…

Optics · Physics 2009-03-17 Ferydon Babaei , Hadi Savaloni

Morphology and performance are conjointed attributes of metamaterials, of which sculptured thin films (STFs) are examples. STFs are assemblies of nanowires that can be fabricated from many different materials, typically via physical vapor…

Optics · Physics 2014-07-01 Akhlesh Lakhtakia , Joseph B. Geddes

We perform combined X-ray tomography and shear force measurements on a cyclically sheared granular system with highly transient behaviors, and obtain the evolution of microscopic structures and the macroscopic shear force during the shear…

Soft Condensed Matter · Physics 2021-02-03 Yi Xing , Jie Zheng , Jindong Li , Yixin Cao , Wei Pan , Jie Zhang , Yujie Wang

We studied the durations and average speeds of videopulses transmitted through chiral sculptured thin films using a finite-difference algorithm. The chiral STF was either linear or possessed an intensity-dependent permittivity. Videopulse…

Optics · Physics 2007-05-23 Joseph B. Geddes , Akhlesh Lakhtakia

The circular Bragg phenomenon is the circular-polarization-state-selective reflection of light in a spectral regime called the circular Bragg regime. In continuation of an expository review on this phenomenon published in 2014, an album of…

Optics · Physics 2025-04-11 Akhlesh Lakhtakia

The propagation of the solitary waves in the Bragg grating formed by array of thin dielectric films is considered. We assume that the thin films of contain the resonant molecules, which are evolved according to two-level atoms model, which…

Pattern Formation and Solitons · Physics 2007-05-23 Andrei I. Maimistov

A new mechanism of Bragg reflection is identified, one that, remarkably, occurs in a uniform medium and relies on resonant tuning of the medium's parameters. Due to uniformity, reflection ensues over a broad wavelength range, much like a…

Optics · Physics 2023-03-22 Martin W. McCall , Stefanos Fr. Koufidis
‹ Prev 1 2 3 10 Next ›