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In this work, the transmittance spectrum for a defective one-dimensional photonic crystal was calculated. The crystal was composed of alternating GaAs and SiO2 layers, and its cavity was infiltrated by escherichia coli bacteria, which was surrounded by thin graphene layers. In this study, we assumed that the GaAs dielectric constant depends on the pressure applied. Within the photonic bandgap, a defect mode that tunes to decreasing wavelengths, as pressure increases can be observed. This shift in the transmittance spectrum is coupled with a decrease in the energy stored within the cavity. In addition, when the graphene-layer thickness was increased while maintaining the pressure constant at 0 GPa, the defect mode is tuned to a long wavelength, which favors two confined modes for thicknesses more than 33 nm. [ABSTRACT FROM AUTHOR]

• Hydrostatic pressure rather than temperature modifies the transmittance spectrum. • Cutoff frequency shift to higher frequency regions with increasing pressure. • Report the appearance of new PBG in the transmittance spectrum with the increasing thickness of GaAs layers. In this paper, we theoretically study the optical properties of a one-dimensional photonic crystal composed alternating semiconductor (GaAs) and superconductor (H g B a 2 C a 2 C u 3 O 8 + δ ) layers using the transfer-matrix method and the two-fluid model. Further, we consider that the dielectric constants of both the materials are dependent on the hydrostatic pressure. The results of the simulations clearly reveal that the cutoff frequency may be manipulated through the thicknesses, pressure, and operating temperature of the constituent materials. By increasing temperature while maintaining constant thickness and pressure, the cutoff frequency shifts to lower frequency regions. However, the thickness of the GaAs layers decreases and the cutoff frequency noticeably shifts to higher frequency regions with increasing pressure and thickness of the superconducting layer. In addition, we report the appearance of new photonic band gaps in the transmittance spectrum with the increasing thickness of the GaAs layers. [ABSTRACT FROM AUTHOR]

In this study, we calculate the photonic band structure for a honeycomb two-dimensional photonic crystal lattice composed triangular holes embedded in GaAs. We assume that the GaAs dielectric function depends on the applied hydrostatic pressure and temperature. The plane wave expansion method is used to calculate the PBS for transverse electric (TE) and transverse magnetic (TM) polarizations. At constant temperature, we find that if the hydrostatic pressure increases, the PBS for both polarizations shifts to higher energies without modifying the gap width. On removing a triangular hole from the structure, both gap position and width remain unchanged for TM polarizations with the presence of a defective band whose energy is tuned to pressure increases. [ABSTRACT FROM AUTHOR]

Abstract We theoretically calculate the transmittance spectrum of TE polarization in a one-dimensional photonic crystal that is embedded in air, composed alternating layers of the YBa 2 Cu 3 O 7− x superconductor and the BaTiO 3 dielectric, using the transfer matrix method. In the first part of this study, we found the transmittance spectrum of the regular structure (without defects). We observe that new photonic band gaps (PBGs) can be observed with a continuous increase in width by increasing the thickness of the superconductor layer and by maintaining the temperature and the thickness of the dielectric in case of normal incidence. By increasing the temperature while maintaining the layer thickness fixed, the dielectric constant of the superconductor can be increased, resulting in a small shift of the transmittance spectrum at long wavelengths. In addition, the PBG widths are observed to be sensitive to an increase in the angle of light incidence. In the second part of this study, the translational symmetry of the crystal is broken by inserting a YBa 2 Cu 3 O 7− x defective layer. Further, we demonstrate the existence of a defective mode in the visible range within the PBG. By increasing the thickness of the defective layer, this defective mode can be observed at long wavelengths. Additionally, the defect mode can be tuned by increasing the temperature and by maintaining a constant crystal thickness. We can also observe a shift to short wavelengths of the defect mode while increasing the angle of incidence. [ABSTRACT FROM AUTHOR]

In this paper, we study the effects of hydrostatic pressure, temperature and angle of incidence on the transmittance spectrum of TE mode of a one-dimensional photonic crystal, using the transfer-matrix method. We consider that the crystal is formed by alternated layers of air and GaAs , with the dielectric constant of GaAs as a function of the temperature and pressure applied. We found that the spectrums dependence on temperature is negligible, the optical response of the system is due mainly to the pressure applied. When increasing the hydrostatic pressure, the spectrum shifts to a short-wavelength, which is caused by the decrease of the dielectric constant of GaAs . These results agree with the electromagnetic variational theorem. We also found if the angle of incidence of the modes increases, the band width increases compared to the normal incidence modes. [ABSTRACT FROM AUTHOR]

In this work by using the transfer matrix method, we studied the effects of applied hydrostatic pressure and temperature on the defect mode in the transmittance spectrum of a one-dimensional photonic crystal consisting of alternating layers of GaAs and Ga 0.7 Al 0.3 As. We consider that the defect is GaAs with a dielectric function that depends on both pressure and temperature. We have found that the dependence of the spectrum with temperature is negligible. However, the notable changes are mainly due to variations in the dielectric constant of the GaAs layers caused by the hydrostatic pressure. The defect mode has a shift at short wavelengths, with an increase in the quality factor when increasing the pressure due to the decrease in the dielectric constant of GaAs. The results found are in accordance with the electromagnetic variational theorem. [ABSTRACT FROM AUTHOR]

In this work using the plane wave expansion method we study the effects of hydrostatic pressure and temperature on the defect mode in the band structure of a one-dimensional photonic crystal. This crystal made of alternating layers of GaAs and air, it is considered that the defect is GaAs with a dielectric constant as a function of pressure and temperature. It is found within the gap of forbidden frequencies the presence of a defect mode, which presents a shift to high frequencies as the pressure increases due to a decrease in the dielectric constant of GaAs . These results are in accordance with the electromagnetic variational theorem. Additionally, it is found that increasing the defect thickness increases the number of modes within the gap of prohibited frequencies. [ABSTRACT FROM AUTHOR]

This work uses the Guided-Mode Expansion method to calculate the photonic band structure and the quality factor for a photonic slab comprising a hexagonal lattice of air holes embedded in a semiconducting material. We consider that the dielectric constant of the semiconductor changes with pressure at a fixed temperature. Using the supercell technique, we removed a row of air holes from the slab to obtain a confined waveguide whose frequency increases with pressure. However, the quality factor decreases with the increase in the applied pressure. [ABSTRACT FROM AUTHOR]

In this work, we calculate photonic band structure for a defective two-dimensional photonic crystal using plane wave expansion method and supercell technique. The photonic crystal comprises circular GaAs cylinders arranged in a two-dimensional hexagonal lattice embedded in an air background in which circular and triangular GaAs defects are inserted. Within the photonic band gap, we can observe a defect mode, whose electric field intensity exhibits a bipolar pattern confined around the defect. If we increase pressure while keeping the GaAs dielectric constant at a constant temperature, we observe that the defective modes shift toward higher frequencies without changing the width of the photonic band gap. Moreover, increasing the radius of the circular GaAs defect favors the appearance of a new defective mode within the photonic band gap. However, if we increase the length of the triangular defect, only a single defect mode may be observed at frequencies close to the air band. We hope that these findings can be considered for the development of new photonic devices. [ABSTRACT FROM AUTHOR]

In this work, we theoretically calculate the transmittance spectra for a one-dimensional photonic quasicrystal composed of a high-temperature superconductor and a semiconductor. The materials are organized based on the Octonacci sequence; in addition, we consider the dependence of dielectric constants and layer thicknesses on the applied pressure. When the temperature increases, the transmittance spectra shift toward shorter frequencies, coupled with a decrease in the cutoff frequency at different Octonacci sequence values. When the pressure increases, the layer thicknesses of the materials decrease, bringing about a shift toward higher transmittance spectra and cutoff frequencies. We also noticed that an increase in the layer thickness results in the maximization and emergence of new photonic band gaps. [ABSTRACT FROM AUTHOR]

In this work, we study the transmittance spectrum in the THz range for one-dimensional photonic crystal surrounded by air. For this purpose, we assumed that the unit cell of the photonic crystal was governed by the Dodecanacci sequence, constituting of superconducting and semiconducting materials. Herein, the dielectric constant of the superconductor depended on hydrostatic pressure and temperature. Conversely, for the semiconductor, we considered its dispersive effects, where both the plasma frequency and dielectric constant depended on pressure and temperature. Through the transfer matrix method and two-fluid model, we observed that the transmittance peaks split as the Dodecanacci sequence increased. The results revealed that the cutoff frequency decreased when the operating temperature was increased. In addition, when the hydrostatic pressure increased at a fixed temperature, both the cutoff frequency and transmittance spectrum shifted toward higher frequencies. [ABSTRACT FROM AUTHOR]

In this work, we calculate the transmittance spectrum within the THz range for a double-period photonic structure composed of polymer materials, whose dielectric constant is a function of the applied pressure. After applying the well-known Transfer Matrix Method, the numerical results reveal that increasing the sequence of the structure favors the appearance of a photonic gap, which exhibits a blueshift when the hydrostatic pressure increases. We also report a redshift in the photonic gap when the thickness of the polymer material layer increases at a fixed pressure value. [ABSTRACT FROM AUTHOR]

• We study the transmittance spectrum in Thue-Morse quasi-periodic one-dimensional photonic crystals. • The number of defect modes increases based on the number of periods. • We have demonstrated that as the pressure increases, the defect modes shift to higher frequencies. Based on the transfer matrix method and the two-fluid model, this study seeks to calculate the transmittance spectrum of a quasi-periodic one-dimensional photonic crystal (PC) composed of semiconductor (GaAs) and superconductor (HgBa 2 Ca 2 Cu 3 O 8 + δ) layers. In particular, the arrangement of the PC layers follows a Thue-Morse sequence with a given periodicity. The critical temperature of the superconductor and the thickness of the semiconductor layers are dependent on the hydrostatic pressure, while the dielectric constant of the semiconductor is a function of both temperature and pressure. Our findings reveal the internal formation of forbidden regions of resonant mode frequencies in the transmittance spectrum and how the transmittance peaks exhibit a splitting after increasing the length of the Thue-Morse sequence. Finally, we demonstrate that as pressure increases the defect modes shift to higher frequency regions. [ABSTRACT FROM AUTHOR]

In this work, we present a theoretical model to calculate the transmittance spectrum of a one-dimensional photonic crystal composed of polymer materials arranged based on a Dodecanacci sequence. In addition, in this crystal, we considered that the dielectric constants of these polymer materials depend on hydrostatic pressure. We calculated the transmittance spectrum in the THz range based on the transfer matrix method. Our numerical results reveal that the transmittance spectrum experiences a blueshift as the hydrostatic pressure increases. Our results also evidence the appearance of photonic gaps when the Dodecanacci sequence increases. Herein, the transmittance spectrum experiences a redshift upon increasing the thickness of the material layers. The results from this work can be applied to the design of narrowband filters. [ABSTRACT FROM AUTHOR]

In this work, we consider the two-fluid model and the transfer-matrix method (TMM) for evaluating the reflectance spectrum in a one-dimensional photonic crystal that is composed by two alternating layers made of superconducting materials HgBa 2 Ca 2 Cu 3 O 8 + δ /BSCCO and a semiconducting layer (GaAs). Our model takes into account the critical temperature dependence on the hydrostatic pressure for the case of HgBa 2 Ca 2 Cu 3 O 8 + δ material, as well as a temperature and pressure dependence on the dielectric constants for case of GaAs semiconductor. We found that at low temperatures, the reflectance spectrum reveals multiple Fano resonances (FR) peaks which disappear as the temperature increases. Further, it is also demonstrated that an increment in the hydrostatic pressure induces a slightly shifts towards short wavelengths without reporting any noticeable changes in the reflectance spectrum. We also found that the number of FR peaks depends on the thickness of the superconducting layer HgBa 2 Ca 2 Cu 3 O 8 + δ and its maximum value of reflectance can be change by increasing the thickness of the BSCCO superconducting layer. We report the occurrence of the phenomenon of electromagnetically induced reflectance in the reflectance spectrum by an increment of the thickness of the GaAs semiconductor layer. [ABSTRACT FROM AUTHOR]

In this work, we use the Guided-Mode Expansion method to calculate the photonic band structure in a photonic crystal slab composed by triangular air holes arranged in a hexagonal lattice. Furthermore, this study focuses on the dependence of the dielectric function of the slab on hydrostatic pressure. The results reveal that when pressure increases, the photonic band structure shifts to higher energies at constant temperatures and constant triangle side lengths. In addition, the width of the TE-like photonic band gap also increases as pressure increases. An increase in band gap width when comparing the photonic band gap for the lattice with unrotated holes against that with rotated holes is observed. [ABSTRACT FROM AUTHOR]

This study calculates the photonic band structures in a one-dimensional photonic crystal composed alternating GaAs and air layers through the plane wave expansion method. When examining the hydrostatic pressure and temperature dependence of the GaAs dielectric function, the photonic band structure clearly shifts to higher frequencies as the pressure increases at a given temperature. Further, if a Ga 1 − x Al x As defect is introduced, it is placed within the photonic band gap in defective modes that are sensitive to Al concentrations and hydrostatic pressure. As the pressure increases, the dielectric constant of the GaAs semiconductor decreases, causing the defective mode to shift towards higher frequencies. [ABSTRACT FROM AUTHOR]

In this paper, we calculate the photonic band dispersion in two-dimensional photonic crystal slabs using the guided-mode expansion method. We consider that the two-dimensional photonic crystal comprises air holes with circular cross-sections distributed in a square lattice. We report an increase in the width of the photonic gap for TE-like modes when we increase the radius of the holes while holding slab thickness constant. Considering the dependence of the dielectric function of the slab on pressure and temperature, as the pressure increases at a fixed temperature, a shift to higher frequencies is observed for the photonic band dispersion in TE-like and TM-like modes. [ABSTRACT FROM AUTHOR]

In this study, we calculate the band diagram for the transverse magnetic polarization, in a two-dimensional photonic crystal with a square lattice comprising cylindrical-shell rods embedded in air. Furthermore, the shells are made of GaAs with a dependence of the dielectric function on temperature and pressure. The results show that as the internal radius of the shell rods increases, the width of the first photonic band gap (PBG) decreases. Moreover, we reported a shift to larger frequencies of the band diagram by increasing the hydrostatic pressure at a fixed temperature value. Additionally, for the defective photonic crystal within the PBG, we may observe a defective mode, in which frequency increases with the pressure. [ABSTRACT FROM AUTHOR]

Using the plane wave expansion and the supercell technique, we calculate the TM band diagram of a waveguide in a honeycomb lattice that composed rods with triangular cross-sections embedded in air. For this study, we use GaAs rods with a dielectric function dependent on pressure and temperature. We report the existence of a defect band within the photonic band gap that presents large confinement for small wave vector values along the line defect. However, for large wave vector values, the defect band approaches the regular crystal bands, thus scattering a greater amount of energy. When the triangles are rotated, greater confinement and smaller scattering of energy is observed than that for unrotated triangles. Additionally, we report that the TM band diagram and the defect band may be tuned to higher frequencies by increasing the applied pressure. [ABSTRACT FROM AUTHOR]