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Dispersion of electromagnetic waves in coaxial cylindrical rippled-wall waveguide including plasma layer
(2022-01-01)
Asadiamiri, F.
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Chaudhary, K.
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Ali, J.
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Bahadoran, M.
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Nejati, Malihe
Electronic technologies, especially in the microwave and terahertz frequency ranges, including plasma show better interaction efficiency and higher output power as compared to apparatus with the vacuum. Also, in these frequency ranges, the plasma-filled high-power waveguides can support TE and TM modes. Therefore, in this study, the dispersion relation of electromagnetic (EM) waves in a new rippled-wall waveguide structure contain the plasma layer and coaxial dielectric geometry is numerically studied. The Maxwell equations and boundary conditions are employed to investigate and analyze the dispersion relation in TM mode for coaxial geometry dielectric rippled-wall waveguide contain the plasma layer. High-frequency radiations are observed from the proposed configuration. It is found that the frequency of the wave increases with a decrease in the corrugation amplitude and period. Moreover, a decrease in frequency is observed with an increase in dielectric radius and a decrease in plasma radius.
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Terahertz cherenkov radiation excited by an electron beam in a cylindrical metallic rippled-wall waveguide
(2020-04-01)
Asadiamiri, F.
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Ali, J.
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Bahadoran, M.
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Chaudhary, K.
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Yupapin, P. P.
The Cherenkov excitation of terahertz (THz) radiation by the interaction of an electron beam with the transverse magnetic modes of electromagnetic waves in a new configuration of cylindrical metallic rippled-wall waveguide (CMRWW) including an unmagnetized degenerate plasma layer and a dielectric rod is studied. In addition, the electric field profiles and the growth rates of these waves are investigated by deriving the wave equation and the dispersion relation for the proposed configuration. The effects of physical parameters such as dielectric and plasma radii, corrugation amplitude, and corrugation period on the dispersion relation, electric field profiles and growth rates of the terahertz radiation are discussed. It is shown that by choosing appropriate parameters of the electron beam and the waveguide, one can generate high power radiation in the terahertz range.
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Consciousness as a quantum dynamic effect
(2016-10-01)
Poznanski, R. R.
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Cacha, L. A.
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Ali, J.
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Aur, D.
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Perez Velazquez, J. L.
Electromagnetic quantum field interactions provide a deeper understanding of the emergence of consciousness through an ontological interpretation of quantum mechanics. Quasiparticle interactions in brain matter can produce "virtual" particles, hitherto mathematical conveniences, which reflect the manifold images of brain activities in terms of effects on charged particles that have physical quantum effect similar to the Aharonov-Bohm effect in quantum field theory. Electromagnetic potentials in the quantum domain pervade the entire brain through causative interactions. The exchange of energy quanta during quantum field interactions emerge as distinct patterns of quasiparticles and their entanglement produces waves of "virtual" particles with periodicities of discrete energies tethered through a common quantum potential as they interact and collectively represent the emergence of self-awareness as a quantum dynamic effect carried on the magnetic vector potential throughout the brain. This is caused by the magnetic dipole moments sensitivity to the phase shifts entrained by the zeitgeber acting on dipolar molecules in interfacial water. The emergence of consciousness is inseparable (spatiotemporally) in the sense that the endogenous electromagnetic field (and therefore the forces acting on the particles) vanish yet neurophenomenologically separate from the physical through the magnetic dipole moments sensitivity to the phase shifts of the coherent system. The subjective aspect of consciousness or phenomenal consciousness facilitates qualia as quantum information through information-physical interactions that metastabilize into rhythms unfolding through resonance into access consciousness as cognizable associable representations of subjective experiences. The transition from subjectivity occurs non-reductively from the microlevel to the macrolevel as a mechanism of spontaneous breaking of symmetry resulting from "photon" behavior of interfacial water instantiated by macroergic effects in the nuclei of neurons through a continuous supply of metabolic energy. The emergence of consciousness in living organisms disappears once autopoietic processes in populations of neurons cease to function.
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Erratum: Laser-Induced Graphite Plasma Kinetic Spectroscopy under Different Ambient Pressures (Chinese Physics Letters (2015) 32:4 043201)
(2015-06-01)
Chaudhary, K.
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Rosalan, S.
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Aziz, M. S.
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Bahadoran, M.
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Ali, J.
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A theoretical model of all-optical switching induced by a soliton pulse in nano-waveguide ring resonator
(2013-01-01)
Nawi, I. N.M.
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Bahadoran, M.
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Ali, J.
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Yupapin, P.
We propose a theoretical model of 1x2 all-optical switching in a silicon nano-waveguide ring resonator induced by a soliton pulse. All-optical switches made by silicon fiber or silicon waveguide have attracted much attention, because the low-absorption wavelength windows of silicon material just match optical fiber communication. However, to achieve all-optical switching in silicon is challenging owing to its relatively weak nonlinear optical properties and require high switching power, which is much higher than the signal power. Such high power is inappropriate for effective on-chip integration. To overcome this limitation, we have used a highly confined nano-waveguide ring resonator structure with soliton pulse input to enhance the nonlinearity and this leads to enhance the effect of refractive index change on the transmission response. The refractive index is changed by controlling the free-carrier concentration through two-photon absorption (TPA) effect. The result indicates that a refractive index change as small as 6.4×10<sup>-3</sup> can reduce the switching power to 2.38 ×10<sup>-6</sup> W. The nano-waveguide ring resonator all-optical switching described here is achieved by using the concept of strong light confinement, and the switching power is approximately three orders of magnitude lower than the available silicon optical switches. Such controllable switch is desired for achieving high performance in nanometer-size planar structures.
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Fast light generation using GaAlAs/GaAs waveguide
(2012-12-01)
Afroozeh, A.
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Bahadoran, M.
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Amiri, I. S.
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Samavati, A. R.
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Ali, J.
Generation of fast light pulses through a nonlinear microring system is an attractive research challenge for high speed optical and quantum computer, optical communication networks and secured communication. In this paper generation of fast light through GaAlAs/GaAs waveguides with fabricated Micro Ring Resonator is reported. Using multistage system, the attosecond pulse can be generated. Simulation results obtained have shown that the generation of a very narrow full-width at half maximum (FWHM) line width and sharp tip is achieved. We propose a new system of multistage micro ring resonators consist of four rings for optical communication system. Here, pulse width of 15 attosecond can be obtained, using proper parameters of the proposed system. © Penerbit UTM Press, Universiti Teknologi Malaysia.
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Light pulse in a modified add-drop optical filter for optical tweezers generation
(2012-01-01)
Aziz, M. S.
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Daud, S.
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Bahadoran, M.
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Ali, J.
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Yupapin, Preecha P.
A new technique of optical tweezer generation and rotation within a modified add-drop optical filter is presented. A proposed system is made up of silica and InGaAsP/InP consisting of linear optical add-drop filter incorporating two nonlinear nanorings on both sides of the micro ring. This particular configuration is known as a "PANDA" ring resonator. Light pulse, for instance, Gaussian, bright and dark solitons are fed into the system through different ports such as drop port and through port. By using the practical device parameters, the simulation results are obtained using the Optiwave and MATLAB programs. Results are obtained by both analytical and numerical methods, which found that the orthogonal solitons can be generated using the proposed system. The tweezer rotation is formed by the spin-up and spin-down states for the input signals, created by using transverse electric and magnetic field within the PANDA ring resonator system. The output signals can be controlled by system parameters such as ring radii, coupling constants, input signals and applied to various applications for tweezer spins such as trapping, transportation and rotation, which can be useful for molecular motor applications. © World Scientific Publishing Company.
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Simulation of soliton amplification in micro ring resonator for optical communication
(2011-01-01)
Afroozeh, A.
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Amiri, I. S.
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Bahadoran, M.
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Ali, J.
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Yupapin, P. P.
A system consisting of a series of micro ring resonator (MRR) is proposed. Optical dark and bright soliton pulses propagating through the nonlinear waveguides are amplified. This system can be used in long distance communication system. The dark and bright soliton is input into the designed system. The nonlinear effect contributes to segregation of continuous soliton pulse into smaller pulses. In this way large bandwidth of optical signals can be obtained. The power amplification occurs when the soliton propagates along the MRRs systems. In this research the concern is the generation of amplified pulse of optical dark and bright soliton while propagating in the MRR device. Simulated results show the amplification of bright soliton in which the input power increases from 0.6 W to 10.9331 W and 7.684 W at the trapped wavelength of 1520.428 nm and 1519.912 nm respectively. © Penerbit UTM Press, Universiti Teknologi Malaysia.
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Molecular transporter system for qubits generation
(2011-01-01)
Amiri, I. S.
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Afroozeh, A.
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Bahadoran, M.
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Ali, J.
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Yupapin, P. P.
A molecular cryptography technique using optical tweezers, is proposed. The optical tweezer transports the molecules in the communication system. The optical tweezer generated by the dark soliton is in the form of a potential well. The dark soliton propagates inside nonlinear microring resonator (NMRR). Transportation of molecules is implemented when the dark soliton is used as input pulse. The input bright soliton control the output signal at the drop port of the system. Output optical tweezers can be connected to the quantum signal processing system consisting of transmitter and the receiver. The transmitter is used to generate the high capacity quantum codes within the series of MRR's and an add/drop filter. The receiver will detect the encoded signals known as quantum bits. The transmitter will generate the entangled photon pair which propagates via an optical communication link. Here the smallest optical tweezer with respect to the full width at half maximum FWHM is 17.6 nm in the form of potential well is obtained and transmitted through quantum signal processor via an optical link. © Penerbit UTM Press, Universiti Teknologi Malaysia.

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