We studied magnetophotonic crystals (MPCs) with introduced magnetic defect layer sandwiched between magnetic and dielectric Bragg mirrors. These magnetophotonic crystals have excellent capabilities to enhance reflection and Kerr rotation simultaneously. By adjusting spatial configuration such as repetition numbers of Bragg mirrors and thickness of magnetic defect layer, we achieved the Kerr rotation angles more than 75˚ and reflection very close to 1. We briefly described the formulation of finite element method (FEM) and transfer matrix method (TMM). The electric field distribution and magnitude of it along the MPCs are simulated using FEM. Using the TMM, we calculated the MO responses of MPCs. With light localization inside the magnetic defect layer and multiple reflections in it, the magneto-optical (MO) responses of these MPCs were significantly increased. The studied structures in this research have high MO responses that make it suitable for designing MO elements in highly sensitive devices and optical telecommunication tools.

An all optical multiplexer will be implemented. Two nonlinear ring resonators with different switching thresholds will be utilized for creating the proposed multiplexer. The proposed structure will have two input and one output port. A control port will be utilized to decide which input data can be illustrated at the output port. The rise time for the proposed structure is about 2 ps. The proposed device can be utilized for implementing all optical systems and networks.

In this paper, a photonic crystal structure for comparing two bits has been proposed. This structure includes four resonant rings and some nonlinear rods. The nonlinear rods used inside the resonant rings were made of a doped glass whose linear and nonlinear refractive indices are 1. 4 and 10-14 m2/W, respectively. Using Kerr effect, optical waves are guided toward the correct output ports. In this study, plane wave expansion and finite difference time domain methods were used for calculation of photonic bandgap and simulation of optical wave propagation, respectively. The size of the proposed structure is 1585 μ m2 which is more compact than the previous works. Furthermore, the obtained maximum delay time is about 2 ps that is proper to highspeed processing. The normalized output power margins for logic 0 and 1 are calculated as 25% and 71%, respectively. According to the obtained results, this structure can be used for optical integrated circuits.

The study investigates the electric field and space charge distributions in propylene carbonate under direct current (DC) applied fields using Kerr effect. Propylene carbonate is known for its high permittivity and is utilised in many applications, including electrochemical systems and dielectric materials. Understanding the behaviour of electric fields and space charge distributions within propylene carbonate is critical for optimising its performance in these applications. In the study, Kerr effect is employed which by applying the DC electric field across the test liquid for measuring the electric field and space charge distributions within the propylene carbonate. The experimental setup involved a controlled application of DC fields, and the Kerr effect measurements were conducted using an optical system. The results show significant understandings into the behaviour of space charges and their influence on the electric field distribution in propylene carbonate. Distinct patterns of charge accumulation and electric field distortion were observed and analysed in the dielectric liquid properties and charge transport mechanisms. The relationship between electric fields and space charges in propylene carbonate under DC conditions has been provided by the findings. The study also shows that the Kerr effect is a useful tool for studying electric field distributions in complex materials.

A compatible theory of relativistic geodesy is quite necessary for future development of any formulation of the subject. In this paper, following recent studies which invoke an idea of relativistic geoid, i. e. the chronometric definition implied by the gravitational redshift, we revisit known calculations on some standard spacetimes. Among all, the notion of frame dragging in the Kerr spacetime and its relationship to the rotative observers needed for the consistent definition of the geoid is analyzed.

In this paper, we proposed an all optical 4-to-2 encoder that has 4 input and 3 output ports. This device generates a 2 bit binary code based on which input port is active. We used nonlinear photonic crystal ring resonators along with optical power splitter for realizing the proposed encoder. In this device the switching rate and area are obtained about 333 GHz and 612μ m2 respectively.