Quasi-Optical Theory of Relativistic Cherenkov Oscillators and Amplifiers with Oversized Electrodynamic Structures

Round 1

Reviewer 1 Report

FOR AUTHORS :

 

Authors propose a paper, whose tittle is "Quasi-optical theory of relativistic Cherenkov oscillators and amplifiers with oversized electrodynamics structures." Concretely, their interest is in developing a theory, and then determine the main characteristics of relativistic Cherenkov amplifiers and oscillators with oversized electrodynamical systems. They demonstrate the prospectives for practical implementation of relativistic surface wave devices in sub millimeter wavebands.

 

The paper is of interest, I find that it really brings something more significant to the subject discussed. I went through the article t vosi that the theory is taken seriously. However, I see negative aspects in this manuscript, such as the fact that the authors indicated far too many self-citations which ultimately lessens the effect on the reader. It would be more relevant to seek to indicate concretely which papers can be read to deepen the subject rather than to roll out an excessively large list of bibliographical references. It is this request which is the subject of point 1/ which I indicate below.

 

1/ Minor: Authors refer to so much self citations: There are at least 23 self citations in the reference list. It is really too much, I ask the authors to reduce this number by approximatively a factor two for instance.

 

2/ Minor: Page 19, lines 552: In Figure 10. The color code is not even mentioned. It is important to have a caption to give the scale of colors, otherwise, it is not of much interest to show colors, I believe. Please indicate the color scale!

 

3/ Minor: Page 25, lines 705: In Figure 14. I make the same remark, you should had a scale of colors please.

 

4/ Minor: Page 27, line 744 : same remark for Figure 15.

 

5/ Minor: Page 32, line 900: same remark for Figure 17.

 

6/ The scale is well indicated on Figure 18 page 36. No remark.

 

7/ Minor: Page 38, line 1051: same remark as 2/ for Figure 19.

 

8/ Minor: Page 39, line 1077: same remark for Figure 20.

 

9/ Minor: I think the authors could have mentioned certain reference articles concerning modern means of determining uncertainties, in accordance with standards widely used elsewhere. It would be good, without necessarily developing, to have a reflection on the errors and the possible uncertainty which would be associated, including because when it comes to theoretical curves precisely, it is I believe the place to approach this subject too. But you could for instance refer to some interesting papers like for instance: T. Doiron and J. Stoup, "Uncertainty and Dimensional Calibrations," J Res Natl Inst Stand Technol. 1997 Nov – Dec, 102(6): 647–676. https://dx.doi.org/10.6028/jres.102.044 and the following: Kacker, R. ; Sommer, K. D. ; Kessel, R. "Evolution of modern approaches to express uncertainty in measurement," Metrologia 44, 513 - 529 (2007). https://doi.org/10.1088/0026-1394/44/6/011 and possibly, this is just a suggestion, those two other recent articles about "uncertainty due to the ISO50 surface determination method for dimensional computed tomography," published in Precision Engineering 61, 82-92 (2020). https://doi.org/10.1016/j.precisioneng.2019.10.004 and this one about "Uncertainty Evaluation on a 10.52 GHz (5 dBm) Optoelectronic Oscillator Phase Noise Performance," published in Micromachines 12(5), 474 (2021). https://dx.doi.org/10.3390/mi12050474

 

After these remarks, I want to emphasize the quality of the proposed article, I think it is adequate to be published in the journal. Jz commends the authors for their work. I move that the article be accepted with minor revisions.

Author Response

We are grateful to Referee I for their valuable comments. According to their recommendations, we somewhat reduced the number of self-citations; however, we believe that significant reduction of references, as proposed by Referee, would not benefit our review, as, in our opinion, it should be comprehensive and cover most of the work done in this field. Instead, we have added some explanations of what can be found in specific paper. We hope that this additional references would not lessened the reader’s the understanding of the quasi-optical approach but would help some of the specific features recognize more deeply.  We only need to mention that during last few years, our original theory was fully confirmed by direct PIC simulations and in many aspects by real physical experiments.

According to the recommendation of Referee I, some color bars were added to the colored figures. References suggested by Referee I concerning data uncertainties and errors are indeed very interesting; however, we believe that this issues are out of scope of our review.

 

On behalf of the Authors,

N.S. Ginzburg.

Reviewer 2 Report

The paper is extremely good, well written and presented.

This referee likes to suggest as further citation the following paper

V. Asgekar and G. Dattoli

THeory Of Cherenkov Free Electron Lasers: An Analytical Treatment

Optics Communications, 255, 309 (2005)

Author Response

We are grateful to the Referee 2 for their valuable comments. According to their recommendations, we added a reference on Dattoli’s paper.

 

On behalf of the Authors,

N.S. Ginzburg.

Reviewer 3 Report

Although this is a quite long paper, it depicts the quasi-optical theory of relativistic Cherenkov oscillators and its application in the submillimeter ultra-high power amplifiers. It is a nice paper and this area will have a nice prospect in the future. The corresponding author Ginsburg has published the related theory and a lots of papers before in PL (2018), APL (2012,2020), PRAB(2018),APL(2012),JAP(2013),PRE(1999),PRL(2013,2016) and IEEE(2021). However, every paper published only part of theory and lack of the enough simulations and modes description so clearly. This paper has concluded all the previous papers and presented us full theory, simulations and future applications on amplifiers or radiation source up to GW power output level in centimeter and/or submillimeter wavelength range. It sounds very well. It is very suitable for electronics to publish it. I believe it will lead the future of a new industry in submillimeter amplifier. This maybe a good solution of the amplifier for 6G industry.

I believe the authors have a nice version for every figure, especially could depicts the figures and corrugation waveguide structures very clearly not only for planar waveguide also for the cylindrical waveguide. From equation (2), we should mark the corrugation in figure 2 from peak to peak as 2b_~, as we did in figure 12, not as b_~ in figure 2.

I checked all the derivations, it is hard to find any mistake. We are luck the authors best contributions. For the scientists, alphabets or symbols are always not enough to express our physical variables. Every people has their own habits to use their familiar expressions. Most people use A as the amplitude of wave component, the author likes C, use C+ as forward component, C- as backward component. It is OK! I don’t know whether reader could understand the difference between such as the and  in the equations. Of course for the experts there is no any problem.

Author Response

We are very grateful to the Referee 3 for his appreciation of our work and attention to our paper. We have fixed the inconsistency in Fig.2 that he found.

On behalf of the Authors,

N.S. Ginzburg.