Pub Date : 2023-12-13DOI: 10.1007/s11141-023-10278-4
V. V. Zhmur, T. V. Belonenko, E. V. Novoselova, B. S. Suetin
We consider various aspects of interaction of vortices with a barotropic flow. When a vortex interacts with a flow, there exist three variants of the flow-core behavior: rotation, nutational oscillations, and unlimited stretching. In the first two cases, the vortex remains a localized formation, such that the ellipse semiaxes undergo oscillations near certain average values. In the third case, the shape of the vortex varies as follows: one horizontal axis increases indefinitely and the second horizontal axis tends to zero so that the vertical size of the vortex does not change and the vortex itself stretches into a filament in top view, remaining ellipsoidal. As a result, vortex formations, which are called filaments, emerge in the ocean. They emerge from the vortices which are initially almost circular in the horizontal plane and represent structures stretched in one direction and having nonzero vorticity. In this work, an analytical and graphical method for determining the regimes of behavior of three-dimensional ellipsoidal vortices is proposed for the first time for an inhomogeneous horizontal current which is linear with respect to the horizontal coordinates. Conditions for inevitable stretching of the vortices into filaments are studied. It is established that the vortex stretching is manifested in spots (domains) on 60–67% of the world ocean surface and the characteristic dimensions of these spots amount to about 200 km. The vortex stretching into filaments ensures energy pumping from mesoscale processes to submesoscale ones. According to the global oceanic reanalysis GLORYS12V1, the domain distributions in the World Ocean are plotted. It is shown that irrespective of the spatial-averaging scales, the integral area of regions in which the mesoscale vortices can stretch into filaments is dominant.
{"title":"On the Stretching of Mesoscale Vortices into Filaments and their Distribution over the Ocean Surface","authors":"V. V. Zhmur, T. V. Belonenko, E. V. Novoselova, B. S. Suetin","doi":"10.1007/s11141-023-10278-4","DOIUrl":"https://doi.org/10.1007/s11141-023-10278-4","url":null,"abstract":"<p>We consider various aspects of interaction of vortices with a barotropic flow. When a vortex interacts with a flow, there exist three variants of the flow-core behavior: rotation, nutational oscillations, and unlimited stretching. In the first two cases, the vortex remains a localized formation, such that the ellipse semiaxes undergo oscillations near certain average values. In the third case, the shape of the vortex varies as follows: one horizontal axis increases indefinitely and the second horizontal axis tends to zero so that the vertical size of the vortex does not change and the vortex itself stretches into a filament in top view, remaining ellipsoidal. As a result, vortex formations, which are called filaments, emerge in the ocean. They emerge from the vortices which are initially almost circular in the horizontal plane and represent structures stretched in one direction and having nonzero vorticity. In this work, an analytical and graphical method for determining the regimes of behavior of three-dimensional ellipsoidal vortices is proposed for the first time for an inhomogeneous horizontal current which is linear with respect to the horizontal coordinates. Conditions for inevitable stretching of the vortices into filaments are studied. It is established that the vortex stretching is manifested in spots (domains) on 60–67% of the world ocean surface and the characteristic dimensions of these spots amount to about 200 km. The vortex stretching into filaments ensures energy pumping from mesoscale processes to submesoscale ones. According to the global oceanic reanalysis GLORYS12V1, the domain distributions in the World Ocean are plotted. It is shown that irrespective of the spatial-averaging scales, the integral area of regions in which the mesoscale vortices can stretch into filaments is dominant.</p>","PeriodicalId":748,"journal":{"name":"Radiophysics and Quantum Electronics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138686072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-13DOI: 10.1007/s11141-023-10280-w
A. A. Abrashkin, E. N. Pelinovsky
By convention, water waves are studied under the assumption of their potentiality. This approximation is not always valid in natural conditions. The vorticity is introduced by shear currents, which are ubiquitous in the ocean. It is also generated in the near-surface layer as a result of wind action. When these factors are taken into account, the models developed for potential waves require refinement and generalization. This paper is devoted to a review of advances in the field of analytical description of surface vortical waves in deep water. The presentation is based on the Lagrangian approach. The focus is on the Gerstner wave, a particular exact solution of the Euler equation. Two ways of its generalization are discussed. The first suggests consideration of weakly nonlinear steady waves with a more general vorticity distribution (Gouyon waves). The second way is to construct exact solutions for waves with inhomogeneous and non-stationary pressure distribution on a free surface (generalized Gerstner waves).
{"title":"Two Ways to Generalize Gerstner Waves in the Theory of Waves in Deep Water","authors":"A. A. Abrashkin, E. N. Pelinovsky","doi":"10.1007/s11141-023-10280-w","DOIUrl":"https://doi.org/10.1007/s11141-023-10280-w","url":null,"abstract":"<p>By convention, water waves are studied under the assumption of their potentiality. This approximation is not always valid in natural conditions. The vorticity is introduced by shear currents, which are ubiquitous in the ocean. It is also generated in the near-surface layer as a result of wind action. When these factors are taken into account, the models developed for potential waves require refinement and generalization. This paper is devoted to a review of advances in the field of analytical description of surface vortical waves in deep water. The presentation is based on the Lagrangian approach. The focus is on the Gerstner wave, a particular exact solution of the Euler equation. Two ways of its generalization are discussed. The first suggests consideration of weakly nonlinear steady waves with a more general vorticity distribution (Gouyon waves). The second way is to construct exact solutions for waves with inhomogeneous and non-stationary pressure distribution on a free surface (generalized Gerstner waves).</p>","PeriodicalId":748,"journal":{"name":"Radiophysics and Quantum Electronics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138685824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-13DOI: 10.1007/s11141-023-10277-5
A. V. Eliseev
The main role in the current climate change is played by anthropogenic forcings, primarily anthropogenic emissions of greenhouse gases and aerosols. On the global scale, the response of the Earth system to these forcings is close to linear. In particular, it depends mostly on the magnitude of such forcings and only weakly on their nature and spatial localization. However, even with relatively small (in absolute value) external forcings, the response of the characteristics of the Earth system can be essentially nonlinear with the manifestation of tipping points, upon transition through which the behavior of the Earth’s climate changes qualitatively. Examples are given for linear and nonlinear mechanisms of the climate response to external forcings.
{"title":"Linear and Nonlinear Aspects of Climate Response to External Forcings","authors":"A. V. Eliseev","doi":"10.1007/s11141-023-10277-5","DOIUrl":"https://doi.org/10.1007/s11141-023-10277-5","url":null,"abstract":"<p>The main role in the current climate change is played by anthropogenic forcings, primarily anthropogenic emissions of greenhouse gases and aerosols. On the global scale, the response of the Earth system to these forcings is close to linear. In particular, it depends mostly on the magnitude of such forcings and only weakly on their nature and spatial localization. However, even with relatively small (in absolute value) external forcings, the response of the characteristics of the Earth system can be essentially nonlinear with the manifestation of tipping points, upon transition through which the behavior of the Earth’s climate changes qualitatively. Examples are given for linear and nonlinear mechanisms of the climate response to external forcings.</p>","PeriodicalId":748,"journal":{"name":"Radiophysics and Quantum Electronics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138686061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-16DOI: 10.1007/s11141-023-10270-y
V. E. Zapevalov, A. S. Zuev, O.P.Plankin, E. S. Semenov
We consider an example of implementation of a multi-barrel gyrotron. The simplest scheme of the multi-barrel gyrotron combines the advantages of both the canonical gyrotron and the gyrotron with the near-axis beam as the system of formation of helical electron beams and efficient selection of modes synchronous with high gyrofrequency harmonics, respectively, and is attractive from the viewpoint of applications that require moderate power levels. The design of a multi-barrel gyrotron with the possibility of simultaneous generation at frequencies of 263, 395, and 526 GHz is presented. Additionally, the possibility of generating the radiation at a frequency of 594 GHz is considered. Such frequencies are required for DNP/NMR facilities with proton Larmor frequencies of 400, 600, 800, and 900 MHz, respectively. Along with the conventional scheme of radiation output towards the collector, the features of the scheme with the radiation output toward the electron gun are considered.
{"title":"Multi-Barrel Gyrotron for DNP/NMR Spectroscopy","authors":"V. E. Zapevalov, A. S. Zuev, O.P.Plankin, E. S. Semenov","doi":"10.1007/s11141-023-10270-y","DOIUrl":"10.1007/s11141-023-10270-y","url":null,"abstract":"<div><div><p>We consider an example of implementation of a multi-barrel gyrotron. The simplest scheme of the multi-barrel gyrotron combines the advantages of both the canonical gyrotron and the gyrotron with the near-axis beam as the system of formation of helical electron beams and efficient selection of modes synchronous with high gyrofrequency harmonics, respectively, and is attractive from the viewpoint of applications that require moderate power levels. The design of a multi-barrel gyrotron with the possibility of simultaneous generation at frequencies of 263, 395, and 526 GHz is presented. Additionally, the possibility of generating the radiation at a frequency of 594 GHz is considered. Such frequencies are required for DNP/NMR facilities with proton Larmor frequencies of 400, 600, 800, and 900 MHz, respectively. Along with the conventional scheme of radiation output towards the collector, the features of the scheme with the radiation output toward the electron gun are considered.</p></div></div>","PeriodicalId":748,"journal":{"name":"Radiophysics and Quantum Electronics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71909620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-10DOI: 10.1007/s11141-023-10275-7
A. B. Plachenov, N. N. Rosanov
{"title":"Correction to: Pulses of the Electromagnetic Field with a Non-Zero Electric Area","authors":"A. B. Plachenov, N. N. Rosanov","doi":"10.1007/s11141-023-10275-7","DOIUrl":"10.1007/s11141-023-10275-7","url":null,"abstract":"","PeriodicalId":748,"journal":{"name":"Radiophysics and Quantum Electronics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71909798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-10DOI: 10.1007/s11141-023-10274-8
A. D. Slyusareva, M. Yu. Emelin, A. S. Emelina, M. Yu. Ryabikin
We study theoretically the features of the spectra of high-order harmonics of laser radiation generated in an ensemble of aligned diatomic molecules outside the framework of the strong-field approximation. The studies were carried out on the basis of numerical calculations within the framework of a model given by a two-center generalization of the Yukawa potential. Influence of the interference of contributions from different electron trajectories and the ion core potential on the accuracy of extracting spectroscopic information about the state of the nuclear subsystem of a molecule using high temporal resolution nonlinear spectroscopy based on the analysis of multicenter effects in the spectra of high-order harmonics has been explored.
{"title":"Coulomb and Quantum Interference Effects in the Spectra of High-Order Harmonics Generated by Aligned Molecules","authors":"A. D. Slyusareva, M. Yu. Emelin, A. S. Emelina, M. Yu. Ryabikin","doi":"10.1007/s11141-023-10274-8","DOIUrl":"10.1007/s11141-023-10274-8","url":null,"abstract":"<div><div><p>We study theoretically the features of the spectra of high-order harmonics of laser radiation generated in an ensemble of aligned diatomic molecules outside the framework of the strong-field approximation. The studies were carried out on the basis of numerical calculations within the framework of a model given by a two-center generalization of the Yukawa potential. Influence of the interference of contributions from different electron trajectories and the ion core potential on the accuracy of extracting spectroscopic information about the state of the nuclear subsystem of a molecule using high temporal resolution nonlinear spectroscopy based on the analysis of multicenter effects in the spectra of high-order harmonics has been explored.</p></div></div>","PeriodicalId":748,"journal":{"name":"Radiophysics and Quantum Electronics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71909799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-10DOI: 10.1007/s11141-023-10272-w
G. F. Zargano, A. V. Kharlanov
We consider excitation of electromagnetic oscillations of a homogeneous dielectric ball by a radial dipole, oscillations forming a periodic sequence of radio pulses. It is shown that at high frequencies the field distribution is close to the field distribution of the eigenoscillations corresponding to these frequencies, whereas the neighboring harmonics also have an impact at low frequencies. It is also shown that an action at low frequencies characterized by a low Q-factor is needed for exciting short radio pulses in the resonator.
{"title":"Excitation of Electromagnetic Oscillations of a Dielectric Ball by a Complex Oscillation of a Radial Dipole","authors":"G. F. Zargano, A. V. Kharlanov","doi":"10.1007/s11141-023-10272-w","DOIUrl":"10.1007/s11141-023-10272-w","url":null,"abstract":"<div><div><p>We consider excitation of electromagnetic oscillations of a homogeneous dielectric ball by a radial dipole, oscillations forming a periodic sequence of radio pulses. It is shown that at high frequencies the field distribution is close to the field distribution of the eigenoscillations corresponding to these frequencies, whereas the neighboring harmonics also have an impact at low frequencies. It is also shown that an action at low frequencies characterized by a low Q-factor is needed for exciting short radio pulses in the resonator.</p></div></div>","PeriodicalId":748,"journal":{"name":"Radiophysics and Quantum Electronics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71909801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-10DOI: 10.1007/s11141-023-10276-6
I. I. Yusipov, S. V. Denisov, M. V. Ivanchenko
A study of open quantum systems and dynamical regimes that emerge in such systems is an actively developing field of the theoretical and experimental physics. Although the bifurcation analysis and the theory of dynamical chaos are very important branches of nonlinear dynamics, their use for describing the processes occurring in open dissipative quantum systems has been restricted until recently. In this work, we present a review of recent results on the generalization of the methods of the oscillation theory for such systems. We present quantum analogs of the classical bifurcations, which are observed in the structural changes of the asymptotic density matrix, namely, the pitchfork bifurcation, saddle-node bifurcation, transition to quantum chaos via a period-doubling cascade, and the Neimark–Sacker bifurcation. We also consider numerical characteristics of dissipative quantum chaos. The largest quantum Lyapunov exponent, which is based on analyzing the divergence rate of the initially close quantum trajectories, allows one to numerically study the structure of the regular and chaotic domains of various open quantum systems. Numerical characteristics of dissipative quantum chaos, which can be observed in a physical experiment, are also considered. It is shown that the qualitatively different statistics of the distribution of times between the successive emissions of individual photons by the system take place for the regular and chaotic regimes in an open quantum cavity.
{"title":"Bifurcations and Chaos in Open Quantum Systems","authors":"I. I. Yusipov, S. V. Denisov, M. V. Ivanchenko","doi":"10.1007/s11141-023-10276-6","DOIUrl":"10.1007/s11141-023-10276-6","url":null,"abstract":"<div><div><p>A study of open quantum systems and dynamical regimes that emerge in such systems is an actively developing field of the theoretical and experimental physics. Although the bifurcation analysis and the theory of dynamical chaos are very important branches of nonlinear dynamics, their use for describing the processes occurring in open dissipative quantum systems has been restricted until recently. In this work, we present a review of recent results on the generalization of the methods of the oscillation theory for such systems. We present quantum analogs of the classical bifurcations, which are observed in the structural changes of the asymptotic density matrix, namely, the pitchfork bifurcation, saddle-node bifurcation, transition to quantum chaos via a period-doubling cascade, and the Neimark–Sacker bifurcation. We also consider numerical characteristics of dissipative quantum chaos. The largest quantum Lyapunov exponent, which is based on analyzing the divergence rate of the initially close quantum trajectories, allows one to numerically study the structure of the regular and chaotic domains of various open quantum systems. Numerical characteristics of dissipative quantum chaos, which can be observed in a physical experiment, are also considered. It is shown that the qualitatively different statistics of the distribution of times between the successive emissions of individual photons by the system take place for the regular and chaotic regimes in an open quantum cavity.</p></div></div>","PeriodicalId":748,"journal":{"name":"Radiophysics and Quantum Electronics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71909712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-10DOI: 10.1007/s11141-023-10273-9
K. V. Vlasova, A. I. Makarov, N. F. Andreev
We show that the strong spatial inhomogeneity of absorption (the change from the maximum to the minimum value was more than 50 times on a spatial scale of the order of 200–300 μm), which was observed in our earlier studies of ultrapure synthetic quartz glasses and a synthetic quartz crystal at a wavelength of 1070 nm, can be related to an inhomogeneous spatial distribution of the redox state of iron traces. Using experimental data on absorption of metal impurities in the studied glasses, we present a calculation of the iron ion concentration, which is of the order of a few ppb. This is several times better than the limit of detection of the mass spectrometry method used for certification of ultrapure quartz glasses. Based on the results of the mass spectrometry measurements of concentrations given by manufacturers and the values of the maximum (10−5 cm−1) and minimum (10−7 cm−1) absorption coefficient we have measured, we calculated the maximum possible concentrations of the Fe2+ and Cu2+ ions and OH groups in quartz glasses and hydrothermal synthetic crystalline quartz.
{"title":"On the Problem of Inhomogeneous Spatial Distribution of the Redox Index of Polyvalent Iron Ions in the Volume of Ultrapure Synthetic Quartz Materials","authors":"K. V. Vlasova, A. I. Makarov, N. F. Andreev","doi":"10.1007/s11141-023-10273-9","DOIUrl":"10.1007/s11141-023-10273-9","url":null,"abstract":"<div><div><p>We show that the strong spatial inhomogeneity of absorption (the change from the maximum to the minimum value was more than 50 times on a spatial scale of the order of 200–300 μm), which was observed in our earlier studies of ultrapure synthetic quartz glasses and a synthetic quartz crystal at a wavelength of 1070 nm, can be related to an inhomogeneous spatial distribution of the redox state of iron traces. Using experimental data on absorption of metal impurities in the studied glasses, we present a calculation of the iron ion concentration, which is of the order of a few ppb. This is several times better than the limit of detection of the mass spectrometry method used for certification of ultrapure quartz glasses. Based on the results of the mass spectrometry measurements of concentrations given by manufacturers and the values of the maximum (10<sup>−5</sup> cm<sup>−1</sup>) and minimum (10<sup>−7</sup> cm<sup>−1</sup>) absorption coefficient we have measured, we calculated the maximum possible concentrations of the Fe<sup>2+</sup> and Cu<sup>2+</sup> ions and OH groups in quartz glasses and hydrothermal synthetic crystalline quartz.</p></div></div>","PeriodicalId":748,"journal":{"name":"Radiophysics and Quantum Electronics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71909713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-10DOI: 10.1007/s11141-023-10271-x
V. Yu. Zaslavsky, M. D. Proyavin, D. I. Sobolev, I. V. Zheleznov, A. M. Malkin, A. S. Sergeyev, V. E. Kotomina, A. A. Orlovsky, N. S. Ginzburg
We present the results of theoretical and experimental studies of the surface-wave Ka-band resonators which are formed by sections of cylindrical waveguides with single-period wall corrugations. The electrodynamic characteristics of such resonance cavities are analyzed within the quasioptical approach and three-dimensional simulation by the finite-difference time-domain method. The results of the theoretical analysis agree quite well with the experimentally measured frequency dependences of the reflection coefficients, which demonstrate the existence of surface modes with different numbers of longitudinal field variations. The measured Q-factors and frequencies of the above-specified modes corresponded well to the calculated values. In order to perform “cold” electrodynamic tests, wideband waveguide converters of the TE mode of the standard rectangular waveguide to the TM mode of an oversized cylindrical waveguide, which have a sufficiently low level of ohmic loss at a conversion efficiency exceeding 95% in the 34–40 GHz frequency range, were manufactured by the the 3D printing method.
{"title":"Observation of Excitation of Eigenmodes in Surface-Wave Resonators Having the Cylindrical Geometry","authors":"V. Yu. Zaslavsky, M. D. Proyavin, D. I. Sobolev, I. V. Zheleznov, A. M. Malkin, A. S. Sergeyev, V. E. Kotomina, A. A. Orlovsky, N. S. Ginzburg","doi":"10.1007/s11141-023-10271-x","DOIUrl":"10.1007/s11141-023-10271-x","url":null,"abstract":"<div><div><p>We present the results of theoretical and experimental studies of the surface-wave <i>K</i><sub>a</sub>-band resonators which are formed by sections of cylindrical waveguides with single-period wall corrugations. The electrodynamic characteristics of such resonance cavities are analyzed within the quasioptical approach and three-dimensional simulation by the finite-difference time-domain method. The results of the theoretical analysis agree quite well with the experimentally measured frequency dependences of the reflection coefficients, which demonstrate the existence of surface modes with different numbers of longitudinal field variations. The measured Q-factors and frequencies of the above-specified modes corresponded well to the calculated values. In order to perform “cold” electrodynamic tests, wideband waveguide converters of the TE mode of the standard rectangular waveguide to the TM mode of an oversized cylindrical waveguide, which have a sufficiently low level of ohmic loss at a conversion efficiency exceeding 95% in the 34–40 GHz frequency range, were manufactured by the the 3D printing method.</p></div></div>","PeriodicalId":748,"journal":{"name":"Radiophysics and Quantum Electronics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71909714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}