The nanotechnology field plays an important role in the improvement of dental implant surfaces. However, the different techniques used to coat these implants with nanostructured materials can differently affect cells, biomolecules and even ions at the nano scale level. The aim of this study is to evaluate and compare the structural, biomechanical and histological characterization of nano titania films produced by either modified laser or dip coating techniques on commercially pure titanium implant fixtures. Grade II commercially pure titanium rectangular samples measuring 35 × 12 × 0.25 mm length, width and thickness, respectively were coated with titania films using a modified laser deposition technique as the experimental group, while the control group was dip-coated with titania film. The crystallinity, surface roughness, histological feature, microstructures and removal torque values were investigated and compared between the groups. Compared with dip coating technique, the modified laser technique provided a higher quality thin coating film, with improved surface roughness values. For in vivo examinations, forty coated screw-designed dental implants were inserted into the tibia of 20 white New Zealand rabbits' bone. Biomechanical and histological evaluations were performed after 2 and 4 weeks of implantation. The histological findings showed a variation in the bone response around coated implants done with different coating techniques and different healing intervals. Modified laser-coated samples revealed a significant improvement in structure, surface roughness values, bone integration and bond strength at the bone-implant interface than dip-coated samples. Thus, this technique can be an alternative for coating titanium dental implants.

Surface plasmon resonance (SPR) based fiber optic sensor with two types of plasmonic metals (gold and silver) are theoretically studied and implemented experimentally. Performance characteristics like sensitivity, signal to noise ratio, the figure of merit, and resolution are evaluated for both simulated and fabricated sensor. The results of theoretical and experimental studies and also between the sensor with the gold layer and that with silver have been compared. Sensitivity is larger for the sensor with the gold layer while the signal to noise ratio and figure of merit are larger for the sensor with the silver layer for both the experimental and theoretical studies. The resolution is slightly larger for the sensor with the gold layer and there is some difference between the resolution of the simulated and that of the fabricated sensor.

The usage of data transmission through Optical Fiber is highly preferred in every area where transferring of data is needed from one end to another. Moreover, nowadays the infrastructure of telecommunications is in good shape and size to handle data transmission through its optical fibers which have low attenuation and higher bandwidth. The seeking of data rate higher than 100Gbit/second and above has been increased to build it in urban and rural areas, and for long and short hauls. Consequently, the current goal is to propel this transmission system into the next appropriated level to avoid any decline of the optical infrastructure than its current capacity. To fulfill increased demand for bandwidth in Broadband services one of the most trusted technology is the Orthogonal Frequency Division Multiplexing (OFDM). The Orthogonal Frequency Division Multiplexing has been placed on-demand in optical communication, it is used in Long haul transmission Format in Direct and Coherent detection. OFDM has many features and abilities can boost the optical fiber performance by eliminating several limits of conventional Optical Fiber communication. OFDMA has polarization mode dispersion (PMD) and chromatic dispersion (CD) which are considered a big addition to the current systems. In addition to that, the easy correlation of the coherent optical OFDM with Wavelength Division Multiplexing (WDM) systems can further advantages in the transmission system such as super bandwidth, high spectral efficiency, and extra data rates. Furthermore, the WDM systems can improve data rate and capacity by using multiple wavelengths over a single fiber. This work aims to bring implementation and to perform a deep-dive study of higher data rates using Direct and Coherent Optical OFDM for long path transmissions. This research starts with a unique user and then extends to the add the OFDM - WDM system to get a data rate of 100 Gbps. Regarding the software portion, the Optisystem simulation tool was used for the design and implementation of the system. Moreover, the modulation type used is QAM for the OFDM signal, and I/Q modulation is deployed, while Coherent and Direct detection is used at the receiving portion. Q Factor, the bit error rate and eye diagram were discussed to study the System’s Performance and Quality. This work found CD-OOFDM is the best system for next generation of optical. The work compared WDM CD-OOFDM with SMF-DCF to DD and CD-OOFDM. In addition to that, it compared WDM CD-OOFDM with SMF-DCF to CD-OODFM with SMF. Therefore, the results showed that WDM CD-OOFDM with SMF-DCF achieved 25 Gbps for four channels of the WDM system at 120km channel, where the carrier frequencies were from 193.05THz to 193.2THz.

Surface plasmon resonance (SPR) based fiber optic sensor with three types of bilayer configurations (silver/gold, copper/gold, and aluminum/gold) is theoretically analyzed. Performance parameters like sensitivity, signal to noise ratio, figure of merit, and resolution are evaluated for each configuration. Signal to noise ratio (SNR), and figure of merit (FOM) are enhanced very well for the selected bilayer configurations as the outer gold layer thickness increased, the sensitivity enhanced also but with small frictions while the resolution has decreased slightly.

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Surface Plasmon Resonance (SPR) is the charge density excitation oscillation (surface Plasmon’s, (SP)) caused by the polarized light along with the metal-dielectric interface by agreeing to phase-matching condition between polarized light and SPR. SPR method has unusual advantages like label-free, real-time and high resolutions with less than 10-7 RIU which is not consenting with other sensing methods. Photonic Crystal Fiber (PCF) presents unique features like design elasticity, geometric flexible and extraordinary guiding mechanism which head for better performance contrast conventional optical fibre, Additionally, the presence of air holes gives the possibility to insert multi able materials, that can recognize the interaction of travelling light and materials operatively. Adding the advantages of PCF to the properties of SPR, lead to design very strong and unique devices in different applications. In this paper, the PCF sensor based on SPR technique had been presented. The inner holes of PCF were coated with silver and then filled with air and ethanol. This was achieved theoretically by Finite Element Method (FEM). When the phase-matching condition was achieved at a fixed wavelength, the energy of the core-guided mode is shifted to the plasmon area and a resonant loss peak is observed at this wavelength. The simulated results show that a blue shifting is obtained when the outer air holes of PCF is filling with ethanol while the inner ring is filled with silver nano-particles. The maximum resolution and sensitivity are 5.66*10-4 RIU, 132.3 nm/RIU respectively in the sensing range of air refractive index to ethanol refractive index are obtained. The submitted design could be very useful in many fields like refractive index and temperature sensing applications.

The technological progress in the means of transmission of information is very fast and it became necessary to obtain high speed in data transmission and high rate of data. Therefore, optical communication systems are the leading methods in this field because they cover these needs, but despite all these characteristics, there is a problem, And we will get rid of this problem in practice in this research through the use of two separate and different wavelengths and connect them to the Wavelength Division Multiplexing and send them to a distance of 3 Km and calculate the amount of dispersion in the signal to the outside of the Optical spectrum analyzer with and without Optical Fiber Bragg Gratings.

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