High-performance biosensors based on angular plasmonic of a multilayer design: new materials for enhancing sensitivity of one-dimensional designs

In this study, a theoretical examination is conducted to investigate the biosensing capabilities of different surface plasmon resonance (SPR) based hybrid multilayer structures, which are composed of two-dimensional (2D) materials. The transfer matrix formulation is implemented to calibrate the results of this study. A He-Ne laser of wavelength = 632.8 nm is used to simulate the results. Many permutations and combinations of layers of silver (Ag), aluminum oxynitride (AlON), and 2D materials were utilized to obtain the optimized structure. Ten dielectrics and twelve 2D materials were tested for a highly sensitive multilayer hybrid sensing design, which is composed of the prism (Ohara S-FPL53)/Ag/AlON/WS2/AlON/sensing medium. The optimized biosensing design is capable of sensing and detecting analytes whose refractive variation is limited between 1.33 and 1.34. The maximum sensitivity, which is achieved by using the proposed design is 488.2° per RIU. Additionally, the quality factor, figure of merit, detection limit, and qualification limit values of the optimized design were also calculated to obtain a true picture of the sensing capabilities. The designing approach based on the multilayer hybrid SPR biosensors has the potential to develop various plasmonic biosensors that are related to food, chemical, and biomedical engineering fields.

Characteristics of multi-absorption bands in near IR based on a 1D photonic crystal comprising two composite metamaterials

The Matlab program has been utilized in this study to examine the absorption spectral properties of a one-dimensional photonic crystal (1DPCs) comprising two composite metamaterials through near IR wavelengths. The composite metamaterials are designed from Ag of a gyroidal geometry (layer A) and hyperbolic metamaterial (layer B). Therefore, the introduced design is labeled as [Formula: see text] with n and m to define the periodicity of the hyperbolic metamaterial and the whole structure, respectively. The numerical findings have been introduced in the vicinity of the effective medium theory, transfer matrix method and the Drude model as well. In this regard, the numerical results demonstrate the appearance of some spectral absorption bands ranging from 0.7 µm to 3 µm for both TM and TE polarizations. Additionally, these bands are almost insensitive to the changes in the angle of incidence. Interestingly, we have considered the role played by some parameters such as the permittivities and thicknesses of both layers on the introduced absorption bands. Finally, we believe that the investigated results could be promising through many applications such as wavelength selective absorbers, solar energy, and smart windows as well.

Optical absorption performance of CZTS/ZnO thin film solar cells comprising anti-reflecting coating of texturing configuration

This paper introduces a novel design of a thin-film solar cell based on CZTS and ZnO composite materials with the help of ITO as the front contact layer. This study primarily focuses on how the cells' optical absorbance at visible wavelengths can be improved. COMSOL Multiphysics is employed as a powerful tool for the investigation of the numerical simulation. The numerical findings showed that the optimum thicknesses of the ITO and ZnO are 80 and 350 nm, respectively. In this regard, with a normal incidence, a wide range of incoming light wavelengths from 450 nm to 800 nm might result in optical absorption of the examined cell of above 0.9. However, this value decreased significantly to reach less than 0.75 when the angle of incidence increased to 50°. To minimize this reduction, on the top surface of the cell, a texture-designed anti-reflective coating designed from a single period of well-known one-dimensional photonic crystals is deposited. The findings demonstrated that the cell's absorption at normal incidence could reach over 0.96 through the overall incident wavelengths. Therefore, CZTS/ZnO thin-film solar cells with an anti-reflecting coating of texturing configuration showed enormous potential for manufacturing effective solar cells.

A promising ultra-sensitive CO2 sensor at varying concentrations and temperatures based on Fano resonance phenomenon in different 1D phononic crystal designs

Detecting of the levels of greenhouse gases in the air with high precision and low cost is a very urgent demand for environmental protection. Phononic crystals (PnCs) represent a novel sensor technology, particularly for high-performance sensing applications. This study has been conducted by using two PnC designs (periodic and quasi-periodic) to detect the CO2 pollution in the surrounding air through a wide range of concentrations (0-100%) and temperatures (0-180 °C). The detection process is physically dependent on the displacement of Fano resonance modes. The performance of the sensor is demonstrated for the periodic and Fibonacci quasi-periodic (S3 and S4 sequences) structures. In this regard, the numerical findings revealed that the periodic PnC provides a better performance than the quasi-periodic one with a sensitivity of 31.5 MHz, the quality factor (Q), along with a figure of merit (FOM) of 280 and 95, respectively. In addition, the temperature effects on the Fano resonance mode position were examined. The results showed a pronounced temperature sensitivity with a value of 13.4 MHz/°C through a temperature range of 0-60 °C. The transfer matrix approach has been utilized for modeling the acoustic wave propagation through each PnC design. Accordingly, the proposed sensor has the potential to be implemented in many industrial and biomedical applications as it can be used as a monitor for other greenhouse gases.

Monitoring and simulation of the fuel irradiation behavior in nuclear reactors based on phononic crystal structure

We have presented in the current work a novel idea for simulating the irradiation behaviors of the nuclear fuel pellets in nuclear reactors by using a one-dimensional defective phononic crystal (1D-DPnC) design was presented. The transmission spectra of the incident mechanical waves were considered basic data for expressing the characteristics of different nuclear fuel-pellets. Herein, the density, sound speed, and Young's modulus of the fuel-pellets represent the key parameters that are influenced by the irradiation behaviors of these pallets. Mixed plutonium-uranium oxide (MOX) nuclear fuel is considered the main fuel in the present study. In addition, a comparison is performed for this fuel with other types of nuclear fuels. Moreover, the mechanical properties of these MOX-pellets are dependent on the porosity, the ratio of oxygen-to-metal (O/M), and the plutonium (Pu-content). The theoretical treatments depend on the transfers matrix method to compute the transmission spectra through the 1D-DPnC. The numerical findings provided that the MOX-pellet has the highest performance compared to other fuel pellets and with sensitivity equal to 59.388 × 10³ Hz s/m. It was also reported that the effects of the percentage of the O/M and Pu- content in MOX had a minor effect in a comparison with the impact of porosity. The theoretical simulation agreed extremely with the experimental data reported for these nuclear fuels. Because of the close relationship between sound speed and density, this sensor can be utilized to monitor the porosity, O/M, Pu-content, and density of fuel-pellets as a quick and non-destructive evaluation technique in a nuclear fuel fabrication laboratory. This article has proven theoretically that MOX fuel produced from nuclear waste of uranium dioxide and plutonium dioxide gives excellent results compared to other types of nuclear fuels, and this agrees with experimental researches. Thus, it may contribute in preserving the environment from nuclear waste, and this can be considered a novel kind of purification of environmental pollution treatment.

Enhanced Sensitivity of Binary/Ternary Locally Resonant Porous Phononic Crystal Sensors for Sulfuric Acid Detection: A New Class of Fluidic-Based Biosensors

This research presented a comprehensive study of a one-dimensional (1D) porous silicon phononic crystal design as a novel fluidic sensor. The proposed sensor is designed to detect sulfuric acid (H₂SO₄) within a narrow concentration range of 0-15%. Sulfuric acid is a mineral acid extensively utilized in various physical, chemical, and industrial applications. Undoubtedly, its concentration, particularly at lower levels, plays a pivotal role in these applications. Hence, there is an urgent demand for a highly accurate and sensitive tool to monitor even the slightest changes in its concentration, which is crucial for researchers. Herein, we presented a novel study on the optimization of the phononic crystal (PnC) sensor. The optimization process involves a comparative strategy between binary and ternary PnCs, utilizing a multilayer stack comprising 1D porous silicon (PSi) layers. Additionally, a second comparison is conducted between conventional Bragg and local resonant PnCs to demonstrate the design with the highest sensitivity. Moreover, we determine the optimum values for the materials' thickness and number of periods. The results revealed that the ternary local resonant PnC design with the configuration of {silicone rubber/[PSi1/PSi2/PSi3]^N/silicone rubber} is the optimal sensor design. The sensor provided a super sensitivity of 2.30 × 10⁷ Hz for a concentration change of just 2%. This exceptional sensitivity is attributed to the presence of local resonant modes within the band gap of PnCs. The temperature effects on the local resonant modes and sensor performance have also been considered. Furthermore, additional sensor performance parameters such as quality factor, figure of merit, detection limit, and damping rate have been calculated to demonstrate the effectiveness of the proposed liquid sensor. The transfer matrix method was utilized to compute the transmission spectra of the PnC, and Hashin's expression was employed to manipulate the porous silicon media filled with sulfuric acid at various concentrations. Lastly, the proposed sensor can serve as an efficient tool for detecting acidic rain, contaminating freshwater, and assessing food and liquid quality, as well as monitoring other pharmaceutical products.

A combination of angle insensitive stopband/passband filters based on one-dimensional hyperbolic metamaterial quasiperiodic photonic crystals

In the present work, we demonstrate the transmittance properties of one dimensional (1D) quasi-periodic photonic crystals that contain a superconductor material and a hyperbolic metamaterial (HMM). A HMM layer is engineered by the subwavelength undoped and doped Indium Arsenide (InAs) multilayers. Many resonance peaks with angle stability are obtained from the proposed Fibonacci sequence structure using the transfer matrix method (TMM). In this case, the Fibonacci sequence serves as the mainstay in the design of our structure. The permittivity of the utilized superconductor and the HMM are also analyzed, respectively. The numerical findings showed that the incident angle has no effect on the wavelength positions of the resonance peaks. The effects of many parameters such as the superconductor material thickness, Fibonacci sequence number, and sequence type are discussed for the proposed structure. At various operating temperatures and superconductor material types, the transmittance characteristics of the proposed structure were also examined. The designed structure can serve as a combination of pass/stop band filters for near-infrared (NIR) applications.

A theoretical approach for a new design of an ultrasensitive angular plasmonic chemical sensor using black phosphorus and aluminum oxide architecture

In this study, the biosensing capabilities of conventional and hybrid multilayer structures were theoretically examined based on surface plasmon resonance (SPR). The transfer matrix method is adopted to obtain the reflectance spectra of the hybrid multilayer structure in the visible region. In this regard, the considered SPR sensor is configured as, [prism (CaF₂)/Al₂O₃/Ag/Al₂O₃/2D material/Al₂O₃/Sensing medium]. Interestingly, many optimization steps were conducted to obtain the highest sensitivity of the new SPR biosensor from the hybrid structure. Firstly, the thickness of an Al₂O₃ layer with a 2D material (Blue P/WS₂) is optimized to obtain an upgraded sensitivity of 360° RIU^-1. Secondly, the method to find the most appropriate 2D material for the proposed design is investigated to obtain an ultra-high sensitivity. Meanwhile, the inclusion of black phosphorus (BP) increases the sensor's sensitivity to 466° RIU^-1. Thus, black phosphorus (BP) was obtained as the most suitable 2D material for the proposed design. In this regard, the proposed hybrid SPR biosensing design may pave the way for further opportunities for the development of various SPR sensors to be utilized in chemical and biomedical engineering fields.

Periodic and quasi-periodic one-dimensional phononic crystal biosensor: a comprehensive study for optimum sensor design

The resonant acoustic band gap materials have introduced an innovative generation of sensing technology. Based on the local resonant transmitted peaks, this study aims to comprehensively investigate the use of periodic and quasi-periodic one-dimension (1D) layered phononic crystals (PnCs) as a highly sensitive biosensor for the detection and monitoring of sodium iodide (NaI) solution. Meanwhile, a defect layer is introduced defect layer inside the phononic crystal designs to be filled with NaI solution. The proposed biosensor is developed based on the periodic PnCs structure and quasi-periodic PnCs structure. The numerical findings demonstrated that the quasi-periodic PnCs structure provided a wide phononic band gap and a large sensitivity compared to the periodic one. Moreover, many resonance peaks through the transmission spectra are introduced for the quasi-periodic design. The results also show that the resonant peak frequency changes effectively with varying NaI solution concentrations in the third sequence of the quasi-periodic PnCs structure. The sensor can differentiate between concentrations ranging from 0 to 35% with a 5% step, which is extremely satisfying for precise detection and can contribute to a variety of issues in medical applications. Additionally, the sensor provided excellent performance for all the concentrations of the NaI solution. For instance, the sensor has a sensitivity of 959 MHz, a quality factor of 6947, a very low damping factor of 7.19 × 10^-5, and a figure of merit of 323.529.

Heavy metals biosensor based on defective one-dimensional phononic crystals

In recent years, the detection of water pollution with low levels of heavy metals has attracted the great attention of many researchers as a result of the imminent danger of this type of pollution to all mankind. Meanwhile, we introduce a theoretical approach based on the one-dimensional phononic crystals (1D-PnCs) with a central defect layer as a novel platform for the highly sensitive detection of heavy metal pollution in freshwater. Therefore, the creation of a resonant peak in the transmittance spectrum related to this defect layer is highly conceivable. In this regard, the detection of cadmium chloride (CdCl₂) as a dangerous, toxic, and extremely hazardous heavy metal could be investigated based on the small displacement in the position of this resonant peak with the changes in the CdCl₂ concentration. Notably, any change in CdCl₂ concentration has a direct impact on its acoustic properties. The theoretical framework of our research study is essentially based on the 2 × 2 transfer matrix method and the acoustic properties of the constituent materials as well. The optimization of all sensor parameters represents the mainstay of this study to get the best sensor performance. In this regard, the proposed sensor has a remarkably high sensitivity (S = 1904.25 Hz/ppm) over a concentration range of 0 - 10000 ppm. In addition, the sensor has a high quality factor (QF), and figure of merit of 1771.318, and 73529410^-5 (ppm^-1), respectively. Finally, we believe this sensor could be a key component of a feasible platform for detecting low concentrations of different heavy metal ions in freshwater.

Photonic crystal nanostructure as a photodetector for NaCl solution monitoring: theoretical approach

In this research, we have a theoretical simple and highly sensitive sodium chloride (NaCl) sensor based on the excitation of Tamm plasmon resonance through a one-dimensional photonic crystal structure. The configuration of the proposed design was, [prism/gold (Au)/water cavity/silicon (Si)/calcium fluoride (CaF₂)¹⁰/glass substrate]. The estimations are mainly investigated based on both the optical properties of the constituent materials and the transfer matrix method as well. The suggested sensor is designed for monitoring the salinity of water by detecting the concentration of NaCl solution through near-infrared (IR) wavelengths. The reflectance numerical analysis showed the Tamm plasmon resonance. As the water cavity is filled with NaCl of concentrations ranging from 0 g l^-1 to 60 g l^-1, Tamm resonance is shifted towards longer wavelengths. Furthermore, the suggested sensor provides a relatively high performance compared to its photonic crystal counterparts and photonic crystal fiber designs. Meanwhile, the sensitivity and detection limit of the suggested sensor could reach the values of 24 700 nm per RIU (0.576 nm (g l)^-1) and 0.217 g l^-1, respectively. Therefore, the suggested design could be of interest as a promising platform for sensing and monitoring NaCl concentrations and water salinity as well.

A doped-polymer based porous silicon photonic crystal sensor for the detection of gamma-ray radiation

In this research, a theoretical investigation of the one-dimensional defective photonic crystals is considered for the detection of gamma-ray radiation. Each unit cell of the considered one-dimensional photonic crystals (1D PhCs) is composed of two layers designed from porous silicon infiltrated by poly-vinyl alcohol polymer doped with crystal violet (CV) and carbol fuchsine (CF) dyes (doped-polymer) with different porosity. In addition, a single layer of doped-polymer is included in the middle of the designed 1D PhCs to stimulate the localization of a distinct resonant wavelength through the photonic band gap. In particular, the appearance of this resonant mode represents the backbone of our study towards the detection of γ-ray radiation with doses from 0 to 70 Gy. The Bruggeman's effective medium equation, the fitted experimental data to the refractive index of the doped-polymer, and the Transfers Matrix Method (TMM) serve as the mainstay of our theoretical treatment. The numerical findings provide significant contributions to some of the governing parameters such as the thicknesses of the considered materials on the performance of the presented sensor, the effect of incidence angle and the porosity of the considered materials on the resonance wavelength. In this regard, at optimum values of these parameters the sensitivity, quality factor, signal-to-noise ratio, detection limit, sensor resolution, and figure of merit that are obtained are 205.7906 nm RIU^-1, 9380.483, 49.315, 2.05 × 10^-5 RIU, 3.27 × 10^-5, and 2429.31 RIU^-1, respectively. Therefore, we believe that the suggested design could be of significant interest in many industrial, medical, and scientific applications.

One-Dimensional Phononic Crystals: A Simplified Platform for Effective Detection of Heavy Metals in Water with High Sensitivity

Recently, the pollution of fresh water with heavy metals due to technological and industrial breakthroughs has reached record levels. Therefore, monitoring these metals in fresh water has become essentially urgent. Meanwhile, the conventional periodic one-dimensional phononic crystals can provide a novel platform for detecting the pollution of heavy metals in fresh water with high sensitivity. A simplified design of a defective, one-dimensional phononic crystals (1D-PnC) structure is introduced in this paper. The sensor is designed from a lead-epoxy multilayer with a central defect layer filled with an aqueous solution from cadmium bromide (CdBr₂). The formation of a resonant peak through the transmittance spectrum is highly expected. This study primarily aims to monitor and detect the concentration of cadmium bromide in pure water based on shifting the position of this resonant peak. Notably, any change in cadmium bromide concentration can affect the acoustic properties of cadmium bromide directly. The transfer matrix method has been used to calculate the transmission spectra of the incident acoustic wave. The numerical findings are mainly based on the optimization of the cadmium bromide layer thickness, lead layer thickness, epoxy layer thickness, and the number of periods to investigate the most optimum sensor performance. The introduced sensor in this study has provided a remarkably high sensitivity (S = 1904.25 Hz) within a concentration range of (0-10,000 ppm). The proposed sensor provides a quality factor (QF), a resolution, and a figure of merit of 1398.51752, 48,875,750 Hz, and 4.12088 × 10^-5 (/ppm), respectively. Accordingly, this sensor can be a potentially robust base for a promising platform to detect small concentrations of heavy metal ions in fresh water.

Multiplication of photonic band gaps in one-dimensional photonic crystals by using hyperbolic metamaterial in IR range

The light-slowing effect near band endpoints is frequently exploited in photonic crystals to enhance the optical transmittance. In a one-dimensional binary photonic crystal (1DPC) made of hyperbolic metamaterials (HMMs), we theoretically examined the angle-dependent omnidirectional photonic bandgap (PBG) for TM polarization. Using the transfer matrix approach, the optical characteristics of the 1DPC structure having dielectric and HMM layers were examined at the infrared range (IR). As such, we observed the existing of numerous PBGs in this operating wavelength range (IR). Meanwhile, the HMM layer is engineered by the subwavelength dielectric- nanocomposite multilayers. The filling fraction of nanoparticles have been explored to show how they affect the effective permittivity of the HMM layer. Furthermore, the transmittance properties of the suggested structure are investigated at various incident angles for transverse magnetic (TM) and transverse electric polarizations. Other parameters such as, the permittivity of the host material, the filling fraction of nanoparticles, and the thickness of the second layer (HMM) are also taken into account. Finally, we investigated the effect of these parameters on the number and the width of the (PBGs). With the optimum values of the optical parameters of the nanocomposite (NC) layer, this research could open the way for better multi-channel filter photonic crystals.

Transmittance properties of one-dimensional metamaterial nanocomposite photonic crystal in GHz range

We have theoretically demonstrated and explored the transmittance characteristics of a one-dimensional binary photonic crystal composed of metamaterial (MM) and nanocomposite (NC) layers. The NC layer was designed from silver nanoparticles (Ag-NPs) in a host material as Yttrium oxide (Y₂O₃). Using the transfer matrix approach (TMM), the optical properties of a one-dimensional binary periodic structure having MM and NC layers in the Giga Hertz (GHz) range were examined. The filling fractions of nanoparticles have been explored to see their effect on the effective permittivity of NC materials. Furthermore, the transmittance properties of the suggested structure were investigated at various incident angles for the transverse electric (TE) polarization. In addition to that, different parameters, such as the thickness of the MM layer, the permittivity of the host dielectric material, the filling fraction, and the thickness of the NC layer are also taken into account. We also discussed the effect of these parameters on the width of the photonic bandgap (PBG). With the optimum values of the optical parameters of NC layer, this research could open the way for better photonic crystal circuits, splitters, switches and others.

Biosensors based on novel nonlinear delta-function photonic crystals comprising weak nonlinearities

In this research, we propose a novel nonlinear delta-function photonic crystal for detecting sodium iodide (NaI) solution of different concentrations. The suggested structure comprises 50 delta stacks of GaP in an aqueous solution of NaI. These stacks are considered to have weak defocusing nonlinearity in the order of 10^-6 (V/m)^-2. Due to nonlinearity of the design, a defect-like resonance is formed within the photonic band gap. Thus, the detection of NaI with different concentrations can be easily investigated without the inclusion of a defect through the photonic crystal structure. The effects of both the linear part of the refractive index of GaP layers and nonlinear coefficient on the transmittance value are thoroughly discussed. The numerical findings investigate that the resonant peak begins to split at some critical nonlinearity. In our proposed structure, splitting occurs at about - 12 × 10^-6 (V/m)^-2. In this regard, the suggested sensor provides a high sensitivity of 409.7 nm/RIU and a wonderful detection limit of 0.0008.

Hybrid Tamm plasmon resonance excitation towards a simple and efficient biomedical detector of NaI solution

This work presents a theoretical verification for the detection of Sodium iodide (NaI) solution with different concentrations in the vicinity of Tamm plasmon (TP) resonance. The proposed sensing tool is constituted of {prism/Ag/cavity/(GaN/CaF₂)¹⁵/air}. The essential foundation of this study is based on the displacement of the TP resonance by varying the concentration of an aqueous solution of sodium iodide (NaI) that fills the cavity layer. The resonant TP dip is shifted downwards the shorter wavelengths with the increment of the Ag layer thickness. Nevertheless, the resonant TP dip is shifted upwards to longer wavelengths with the increment of NaI refractive index/concentration. Also, the sensitivity of the sensing tool decreases with the increment of the NaI refractive index. However, the minimum result is not less than the value of 9913 nm RIU⁻¹ for a concentration of 25%. Finally, the performance of our sensor in the form of the quality factor, detection limit, and figure of merit showed significant improvements in designing a high-performance liquid and biosensor.

NaI sensor: the suggested design of a NaI photonic crystal sensor that is constituted.

Simple, efficient and accurate method toward the monitoring of ethyl butanoate traces

We introduce in this research a simple, accurate, safe, and efficient design for the detection of ethyl butanoate that be present in the dry exhaled breath. In particular, the presence of ethyl butanoate in the dry exhaled breath could be utilized as a platform for the diagnosing of COVID 19. The main idea of this theoretical investigation is based on the inclusion of a cavity layer between a thin layer of Au and the well-known one-dimension photonic crystals. Accordingly, the cavity layer is filled with dry exhaled breath. The numerical results are investigated in the vicinity of the Drude model and transfer matrix method. The investigated results show the appearance of Tamm plasmon resonance in the reflectance spectrum of our design through the IR region. Such resonant mode provides very high sensitivity with the change in the concentration of ethyl butanoate. We have examined the performance of the proposed sensor by calculating its sensitivity, detection limit, detection accuracy, quality factor and figure of merit. The designed sensor could receive sensitivity of 0.3 nm/ppm or 260,486 nm/RIU, resolution of 7 ppm and quality factor of 969.

MicroPulse® transscleral laser therapy in the management of glaucoma patients

PURPOSE

To evaluate the efficacy and safety of MicroPulse® transscleral laser therapy (TLT) in the management of glaucoma patients.

METHODS

A prospective, interventional, non-comparative case series was conducted in the department of ophthalmology, Ain Shams University Hospital on 61 eyes of 46 patients with various glaucoma types and of severity, ranging from mild to severe. In addition to best-corrected visual acuity (BCVA), intraocular pressure (IOP) and the number of glaucoma medications were recorded before and after treatment, along with the postoperative need for systemic carbonic anhydrase inhibitors (CAI), success rates, number of treatment sessions and postoperative complications. Success was defined as an IOP of 6-18 mmHg or at least a 30% decrease from preoperative IOP in the absence of any vision-threatening complications during the 6-month follow-up period.

RESULTS

MicroPulse TLT was performed on 61 glaucomatous eyes. Eleven of the 61 eyes (18%) that did not achieve IOP between 6-18 mmHg, or at least a 30% decrease from baseline at 6 months, had a repeat MicroPulse TLT session. At 6 months follow-up post a single MicroPulse TLT session, the mean IOP reduction was 35.9 ± 14.2%; and 6 months after the second session, it was 36.2 ± 17.5% (p < 0.001). The success rate after the first session was 73.8% which increased to 78.7% after the second session. The mean anterior chamber (AC) cell reaction was +1.9 ± 0.8 at 1 day, +1.0 ± 0.7 at 1 week, and +0.2 ± 0.4 at 1 month postoperatively. No cells were detected in any of the cases at 3 and 6 months follow-up (p < 0.001). The average number of anti-glaucoma eye drops before MicroPulse TLT was 2.6 ± 1.0. Postintervention, the average number of anti-glaucoma eye drops was 1.7 ± 1.2, and sustained at 6 months follow-up after the last treatment session (p < 0.001). There were no significant complications were noted. One eye developed transient hypotony for 3 months after MicroPulse TLT.

CONCLUSIONS

MicroPulse TLT is safe and effective in lowering IOP in a variety of glaucoma types and severity.

Defect mode tunability based on the electro-optical characteristics of the one-dimensional graphene photonic crystals

New (to the best of our knowledge) photonic crystal optical filters with unique optical characteristics are theoretically introduced in this research. Here, our design is composed of a defect layer inside one-dimensional photonic crystals. The main idea of our study is dependent on the tunability of the permittivity of graphene by means of the electro-optical effect. The transfer matrix method and the electro-optical effect represent the cornerstone of our methodology to investigate the numerical results of this design. The numerical results are investigated for four different configurations of the defective one-dimensional photonic crystals for the electric polarization mode. The graphene as a defect layer is deposited on two different electro-optical materials (lithium niobate and polystyrene) to obtain the four different configurations. The electro-optical properties of graphene represent the main role of our numerical results. In the infrared wavelength range from 0.7 µm to 1.6 µm, the reflectance properties of the composite structures are numerically simulated by varying several parameters such as defect layer thickness, applied electrical field, and incident angle. The numerical results show that graphene could enhance the reflectance characteristics of the defect mode in comparison with the two electro-optical materials without graphene. In the presence of graphene with lithium niobate, the intensity of the defect mode increased by 5% beside the shift in its position with 41 nm. For the case of polystyrene, the intensity of the defect mode increased from 6.5% to 68.8%, and its position is shifted with 72 nm. Such a design could be of significant interest in the sensing and measuring of electric fields, as well as for filtering purposes.

Detection and sensing of hemoglobin using one-dimensional binary photonic crystals comprising a defect layer

Believing that the detection of hemoglobin possesses a vital role in the discovery of many diseases, we present in this work a simple method for sensing and detecting hemoglobin based on one-dimensional photonic crystals. Implementing hemoglobin as a defect layer inside the proposed photonic crystal results in a resonant peak evolving within the bandgaps. The strong dependence of these resonant peaks on concentration and the consequent refractive index are the essential bases of the detection process. The role played by these parameters together with the angle of incidence on performance and efficiency of our sensor is demonstrated. In the vicinity of the investigated results, we demonstrate the values of sensitivity, figure of merit (FOM), signal-to-noise ratio (SNR), and resolution to optimize the performance of our sensor. The numerical results show a significant effect of polarization mode on performance of this sensor. For TE polarization with an angle of incidence equal to 45°, we investigated sensitivity of 167nmRIU^-1, SNR of 0.23, FOM of 0.63RIU^-1, and resolution of 257 nm.

Enabling Device-to-Device Technology in 5G Heterogeneous Networks

5G is the next step in the evolution of mobile communication. The evolving 5G cellular wireless networks are envisioned to provide higher data rates, enhanced end-user quality-of-experience (QoE), reduced end-to-end latency, and lower energy consumption. Device to device (D2D) is one of the key technologies provided to enhance 5G performance. Direct communication between two devices without involvement of any central point (i.e., base station) is defined as device to device (D2D) communication. It is a recommended technique to enhance the network performance of 5G in terms of energy efficiency, throughput, latency, and spectrum utilization. In this chapter, the authors provide a detailed survey on the integration of D2D communication into cellular network especially 5G network. The survey highlights the potential advantages; classifications and application for D2D technology have been indicated. Main D2D standards have been presented. Finally, the chapter addresses main topics that could be related to D2D and indicates all major possible challenges that face most researchers.

One-dimensional defective photonic crystals for the sensing and detection of protein

The sensing of protein is of great importance because of its prominent role in building and repairing tissues. In this work, we present a simple design for the detection and sensing of protein using one-dimensional defective photonic crystals. The main idea of our work is included in the theoretical investigation of the transmittance properties of the resonant mode produced inside the photonic band gap. Our study uses the characteristic matrix method and curve fitting. The main reason for our study is to detect the concentration of a protein solution using an efficient, accurate, and simple method. Here, the defect layer is filled with a protein solution. Our idea depends on two hypotheses, and the first one is based on the appearance of a resonant peak on the photonic band gap. The second one depends on a change in the position of this resonant peak with the concentration of the protein solution. The effect of many parameters on the performance of our sensor, such as the thickness of the defect layer and the sensitivity, is demonstrated. The numerical results could present a simple way to design an accurate, stable, efficient, and low-cost protein sensor compared to other current methods and techniques.

Tunability of two dimensional n-doped semiconductor photonic crystals based on the Faraday effect

In this paper, we theoretically investigate the effect of an external magnetic field on the properties of photonic band structures in two-dimensional n-doped semiconductor photonic crystals. We used the frequency-dependent plane wave expansion method. The numerical results reveal that the external magnetic field has a significant effect on the permittivity of the semiconductor materials. Therefore, the photonic band structures can be strongly tuned and controlled. The proposed structure is a good candidate for many applications, including filters, switches, and modulators in optoelectronics and microwave devices.