Showing 4 results for Transfer Matrix
Hamid Pashaei Adl, Samad Roshan Entezar,
Volume 6, Issue 1 (10-2012)
Abstract
In this paper, the optical properties of one dimensional fractal structures are investigated. We consider six typical fractal photonic structures: the symmetric dual cantor-like fractal structure, the asymmetric dual cantor-like fractal structure, the single cantor-like fractal structure, the symmetric dual golden-section fractal structure, the asymmetric dual golden-section fractal structure and the single golden-section fractal structure. By using the transfer matrix method the transmission spectra of these structures are simulated. The calculation results shows that the transmission spectrum of the symmetric dual cantor-like fractal structure is self-similar and the peak numbers in the transmission spectra of the SDGSFS also follow the principals of special fractal structures. It is also shown that in the symmetric dual golden-section fractal structure the localization of modes which appears within the stop band increases and getting closer to the middle of the gap by increasing the number of string.
Reza Ghayoor, Alireza Keshavarz,
Volume 13, Issue 1 (1-2019)
Abstract
By developing the terahertz (THz) technology, in addition to generators and detectors of THz waves, the existence of some tools such as modulators and filters are needed. THz filters are important tools for various applications in the field of chemical and biological sensors. Linear and nonlinear optical properties of the graphene have attracted lots of attention. In fact graphene exhibits various nonlinear phenomena. Hence in this paper, by entering the graphene to the field of THz and using the graphene nonlinear properties with utilizing the transfer matrix method and transmission properties of a periodic structure containing graphene are investigated. A fairly straightforward computational method allows us to examine the effect of different structural parameters on the transmittance spectrum. Simulation results show that if the graphene nonlinear response in a periodic structure in the presence of a high-intensity THz field is considered, the proposed structure displays two bands of passes and stopping which can improve the design of the filters and controllers of THz waves.
Ferydon Babaei,
Volume 16, Issue 1 (1-2022)
Abstract
In this study, the interaction of surface plasmon polariton and surface exciton at the interface of a plasmonic medium and a dielectric medium with a C-shaped column morphology consisting of exciton molecules theoretically and classically was investigated in the Kretschmann configuration using the transfer matrix method. The optical absorption spectra of surface plasmon polariton, surface exciton, and surface plexciton have been depicted. The results showed that when the surface plasmon polariton frequency is equal to or close to the frequency of the surface exciton, the polariton mode has two branches, high and low. The mode splitting is caused by the interaction of the surface plasmon polariton and the surface exciton. The characteristics of the splitting energy were analyzed at different structural parameters. The being surface of the plasmon, exciton, and plexciton waves and their localization at the interface between plasmonic and dielectric media were proved by the time averaged Poynting vector and the local absorption.
Sarah Bolandnazar, Samad Roshan Entezar,
Volume 17, Issue 1 (1-2023)
Abstract
In this article, we provide a theoretical investigation into the reshaping of flat-top pulses in a one-dimensional, homogeneous, isotropic, finite-size photonic crystal with two defect layers. We use Fourier transform to find frequency and time spectra, and transfer matrix to determine transmission spectra to find the average duration and power of the output pulse. The pulses with a carrier frequency near the defect mode center and a wide frequency spectrum, undergo the most significant reshaping. Reshaping is strongest for narrow pulses with a carrier frequency at defect mode peaks. The maximum power and duration of the output pulse of a spectrally narrow pulse are all proportional to the pulse duration and exhibit extremes at the frequencies of the defect mode peaks. The power and average duration of a spectrally wide pulse's output pulse are not affected by the carrier frequency.
