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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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Dispersion characteristics of terahertz transverse electric mode in a smooth-wall cylindrical waveguide with a degenerate plasma layer
(2020-05-01)
Asadiamiri, F.
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Nejati, M.
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Chaudhary, K.
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Baboli, M.
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Ali, J.
The propagation of transverse electric mode in a cylindrical metallic smooth-wall waveguide contains a dielectric rod and a cold collisionless unmagnetized degenerate plasma layer is analytically investigated in the terahertz frequency region. The dispersion relations of fast and slow waves for this mode are derived and solved numerically. The effects of geometrical and physical parameters such as dielectric, plasma and metal radii, and dielectric permittivity on the dispersion characteristics of terahertz transverse electric mode and its frequency spectrum are studied. It is shown that the decrease of dielectric permittivity and metal radius, and the increase of degenerate plasma radius leads to higher frequency fast waves. It is also indicated that an increase in the dielectric radius results in a decrease in the frequency of fast waves. In addition, it is found that by reducing the dielectric rod radius and with increasing metal radius, the frequency is increased in the slow waves. Finally, it is shown that the increase in dielectric permittivity causes a decrease in the frequency of both fast and slow waves.
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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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Multi wgm light probes generated by distributed panda resonator system
(2016-06-01)
Sappajak, S.
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Patharacorn, P.
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Chaingga, S.
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Yupapin, P. P.
Multi-micro-sensing probes are generated by whispering gallery mode (WGM) of light within a PANDA ring resonator, from which the sensing device model is designed and simulated using the commercial MATLAB and Opti-wave programs. The WGMs are generated by travelling light signals within the nonlinear micro-ring resonator. The specific control of the concerned device parameters is provided, from which the generated WGM probes are obtained and used to form the distributed sensing head, where the exchange between the measurement environments and sensing device parameters can be interpreted to form the required signals. In practice, the output signal can be obtained by using the detected output device (i.e., photodetector) via the add port output signals, where the measurements in terms of phase or wavelength changes can be interpreted relatively to the applied physical content parameters. Results obtained have shown that the linear relationship between angular velocity and the change in wavelength can be achieved, which is useful for sensing device application. In general, the large volume or contents can be employed by using the distributed sensor configuration.
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A comprehensive treatment of parametric effect in a silicon microring resonator
(2016-05-18)
Nawi, I. N.M.
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Ali, J.
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Yupapin, P. P.
Silicon microring resonator provides a new platform to form the building block for all-optical circuits, where it could be integrated on a single chip as a passive or active components. Here, we report a comprehensive treatment of parametric effect in a symmetrical add/drop silicon microring resonator with 5 μm radius operating within telecom wavelength spectrum or C-band ranging from 1530 nm to 1565 nm. The power outputs of the system are analyzed by using transfer matrix method. The FSR and FWHM have been optimized. The results demonstrated here will pave the way towards the new on-chip and chip-to-chip architecture and structure for low power and high bandwidth applications especially for all-optical switch and optical modulator.
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Soliton pulse induces TPA effect in a silicon MRR all-optical switch
(2016-05-18)
Nawi, I. N.M.
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Ali, J.
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Yupapin, P. P.
One of the critical problems in achieving a real practical all-optical switching devices is the requirement for a strong material nonlinearity. A strong material nonlinearity is crucial in order to achieve a low switching power. However, silicon-based all-optical switches require extremely high switching power due to its relatively weak nonlinear optical properties. To overcome this limitation, we have designed an all-optical switch configuration based on silicon microring resonator structure and demonstrated the switching operation based on the nonlinear effects induced by a soliton pulse. The soliton pulse induces free-carrier concentration through two-photon absorption (TPA) effect and this leads to enhance the refractive index change and enhance the nonlinearity of the silicon. Thus, the silicon microring resonator alters the nonlinear phase shift which is required for switching.
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Analysis of temperature sensor in all-pass microring resonator
(2016-03-01)
Mohamad, Azam
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Bahadoran, Mahdi
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Daud, Suzairi
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Chaudhary, Kashif Tufail
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Aziz, M. S.
The temperature sensor using all-pass microrin resonator (APMRR) investigated theoretically and analyzed. An optical bright soliton is used as a probe to study the effect of applied temperature on the light behavior pass through microring waveguide. The split-step Fourier method is used to study the pulse propagation inside the APMRR. Result shows that the rise of temperature on peak amplitude ratio fit with quadratic line in temperature range of 27 oC-37 oC. . The temperature at 30 oC generate higher slope of reduction compare to temperature at 36oC. The amplitude ratio is reduced into 0.6 (-4.4370 dB) when the temperature increased as small as 1 oC. The operating range for all-pass resonator is 97 oC with amplitude reduction of -8.3975 dB.
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Spirit and brain signal analogy for brain science study
(2016-01-01)
Sappajak, S.
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Yupapin, P. P.
A new insight of brain signal oscillation within a brain is proposed using the spirit signal, which is formed by the vector soliton pulse after Big Bang and localized in the Hilbert space. The spirit signal is entered into the suitable brain via the nerve center and linked to the entire body. The spirit signal oscillation can be configured by the propagation of photon within the circular like motion device, which is a nonlinear material device known as a panda ring resonator. A spirit signal is a form of energy and configured by a photon, from which the traveling spirit signal behavior can be described by using the standard time dependent Schrodinger equation. Preliminary results obtained have shown that the use of the spirit signal traveling in the nonlinear ring resonator can be formed and investigated. The proposed spirit signal can be used for brain signal manipulation, which is useful for brain science researches and investigations.
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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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