اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدPeriodic thin-film interference filters as one-dimensional photonic crystals
70
0
0.0
(
0
)
اسأل ChatGPT حول البحث
ﻻ يوجد ملخص باللغة العربية
We review photonic band gap related properties of a simple periodic system of thin dielectric layers. Properties associated with forbidden and allowed bands of such one-dimensional photonic crystals are presented. A revision of forbidden bands properties leads to an omnidirectional Bragg mirror design. The anisotropy of allowed bands suggests the formation of photon-focusing caustics in one-dimensional photonic crystals.
قيم البحث
اقرأ أيضاً
258 -
Thawatchai Mayteevarunyoo (Department of Telecommunicationn Engineering
, Mahanakorn University of Technology
, Bangkok
2008
We report results of a systematic analysis of spatial solitons in the model of 1D photonic crystals, built as a periodic lattice of waveguiding channels, of width D, separated by empty channels of width L-D. The system is characterized by its structu
ral duty cycle, DC = D/L. In the case of the self-defocusing (SDF) intrinsic nonlinearity in the channels, one can predict new effects caused by competition between the linear trapping potential and the effective nonlinear repulsive one. Several species of solitons are found in the first two finite bandgaps of the SDF model, as well as a family of fundamental solitons in the semi-infinite gap of the system with the self-focusing nonlinearity. At moderate values of DC (such as 0.50), both fundamental and higher-order solitons populating the second bandgap of the SDF model suffer destabilization with the increase of the total power. Passing the destabilization point, the solitons assume a flat-top shape, while the shape of unstable solitons gets inverted, with local maxima appearing in empty layers. In the model with narrow channels (around DC =0.25), fundamental and higher-order solitons exist only in the first finite bandgap, where they are stable, despite the fact that they also feature the inverted shape.
It is shown that total reflection for all incident angles does not require a two- or three-dimensional photonic crystal. We demonstrate that a one-dimensional photonic crystal can exhibit total omni-directional reflection for any incident wave within
some frequency region. The formation of the omni-directional gap is discussed and a wide range of realistic fabrication parameters is proposed.
We report on very high enhancement of thin layers absorption through band-engineering of a photonic crystal structure. We realized amorphous silicon (aSi) photonic crystals, where slow light modes improve absorption efficiency. We show through simula
tion that an increase of the absorption by a factor of 1.5 is expected for a film of aSi. The proposal is then validated by an experimental demonstration, showing an important increase of the absorption of a layer of aSi over a spectral range of 0.32-0.76 microns.
One-dimensional magnonic crystals have been implemented as gratings of shallow grooves chemically etched into the surface of yttrium-iron garnet films. Scattering of backward volume magnetostatic spin waves from such structures is investigated experi
mentally and theoretically. Well-defined rejection frequency bands are observed in transmission characteristics of the magnonic crystals. The loss inserted by the gratings and the rejections bands bandwidths are studied as a function of the film thickness, the groove depth, the number of grooves, and the groove width. The experimental data are well described by a theoretical model based on the analogy of a spin-wave film-waveguide with a microwave transmission line. Our study shows that magnonic crystals with required operational characteristics can be engineered by adjusting these geometrical parameters.
The light absorption and transmission of monolayer MoS$_{2}$ in a one-dimensional defective photonic crystal (d-1DPC) is theoretically investigated. The study shows that the strong interference effect decreases photon density in particular areas of t
he microcavity. The d-1DPC can reduce light absorption of monolayer MoS$_{2}$ and enhance light transmission. The impact of monolayer MoS$_{2}$ light absorption on the localization effect of photon is investigated when monolayer MoS$_{2}$ and the organic light-emitting diode are located in the same microcavity. However, monolayer MoS$_{2}$ does not reduce the localization effect of light by regulating the position of monolayer MoS$_{2}$ in the microcavity.
سجل دخول لتتمكن من نشر تعليقات
التعليقات
جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
