Coherent Nonlinear Resonances of Saturated Absorption at Transitions from the Ground 1S0 Atomic State in the Spectroscopy of Unidirectional Waves
Aleksandr Chernenko,
Edward Saprykin
Issue:
Volume 8, Issue 3, September 2020
Pages:
51-60
Received:
30 June 2020
Accepted:
20 July 2020
Published:
19 August 2020
Abstract: The shapes of the saturated absorption resonances at transitions from the ground 1S0 atom state in a gas medium in the field of two unidirectional waves are investigated both analytically and numerically. It is shown for the first time that the spectra of nonlinear resonances are formed by processes in the two-and three-level V-schemes resulting from the degeneracy of the upper P transition state, are qualitatively different at the resonant transition and transitions to the more excited atom states. It is established that the physical causes for differences of these spectra are due to the different degree of branching of the radiation from the excited to the ground state (the degree of openness) of transition. The degree of openness of transition determines the amount of contributions of coherent processes to the resonance shapes both in the system of two levels (coherent population beats) and three levels (nonlinear interference effect).
Abstract: The shapes of the saturated absorption resonances at transitions from the ground 1S0 atom state in a gas medium in the field of two unidirectional waves are investigated both analytically and numerically. It is shown for the first time that the spectra of nonlinear resonances are formed by processes in the two-and three-level V-schemes resulting fr...
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Triangular Rogue Waves and Multi- Wave Trains Generation in a Chameleon Electrical Transmission Line
Bedel Giscard Onana Essama,
Salome Ndjakomo Essiane,
Frederic Biya – Motto,
Mohammed Shabat,
Jacques Atangana
Issue:
Volume 8, Issue 3, September 2020
Pages:
61-73
Received:
9 August 2020
Accepted:
26 August 2020
Published:
23 November 2020
Abstract: In this work, we present a particular nonlinear transmission line called chameleon nonlinear transmission line. In fact, the chameleon’s behavior is related to the fact that without changing its appearance, the line can exhibit alternatively purely right - or left - handed behavior. This transmission line is different to the composite one. So, the goal of this work is to demonstrate that this special line can support the propagation of soliton light pulse subjected to quintic – phase modulation, improve the freak wave’s mechanism of generation and verify the chameleon’s behavior of the line. Consequently, we employ collective coordinate’s theory in order to give a great characterization of the light pulse. Then, we introduce an upgraded function called “type II Ansatz function” with eight collective coordinates compared to the conventional Gaussian Ansatz with six collective coordinates. We show that the two additional coordinates will allow us to improve the technique of measurement of internal excitation leading to the generation of rogue events. Moreover, these coordinates will give supplemental details on frequency shift and chirp distortions during the generation of specific rogue events such as “wall of waves”, tree structures, multi - wave trains, Kuznetsov - Ma breathers, Akhmediev breathers, Peregrine solitons and triangular rogue waves. The stability of the soliton light pulse will be also investigated at specific frequency ranges.
Abstract: In this work, we present a particular nonlinear transmission line called chameleon nonlinear transmission line. In fact, the chameleon’s behavior is related to the fact that without changing its appearance, the line can exhibit alternatively purely right - or left - handed behavior. This transmission line is different to the composite one. So, the ...
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