Mitigating Vortex Splitting by Controlling the Wavefront Isophase Line Curvature of Vector Autofocusing Airy Vortex Beams in Free Space

Round 1

Reviewer 1 Report

In this manuscript, the authors introduced a new parameter to modulate the radial polarization state of the autofocusing Airy vortex beams (AAVB), and the vortex splitting in free space can be effectively mitigated. This manuscript is interesting and I would like to suggest it to be considered for publication on Photonics once the following concerns have been cleared:

 

1. It is better to show related reference for Eq (1).
2. Since the expressions for the x component of the vector AAVBs is very similar to that of the y component, I suggest to combine Eq (2a) and Eq (2b) to make a more concise paper.
3. In Fig. 4e, the cross sections of the intensity are not clear, the authors should consider narrowing the domain of the radius r.
4. On page 6 the first paragraph, the explanation is insufficient as the authors only demonstrate the phenomena while didn't explain why the focal intensity and the main ring radii change in this way.
5. The following new references can be citied:

[1] Zhang, Q., Liu, Z., & Wang, X. Generation and characteristics of an Airy vortex beam from the anomalous vortex beam. Results in Physics, 35, 105389 (2022).

[2] Wu, Y., Xu, C., Qiu, H., Xu, D., & Deng, D. Guiding the optical vortex along predesigned parabolic trajectories from circular symmetric Airy-like beams. Applied Optics, 61(8), 1906-1911 (2022).

[3] Bai, Y., Lv, H., Fu, X., & Yang, Y. Vortex beam: generation and detection of orbital angular momentum. Chinese Optics Letters, 20(1), 012601 (2022).

Author Response

Dear Reviewer，

Thank you for your comments concerning our manuscript entitled: “Mitigating vortex splitting by controlling wavefront isophase line curvature of vector autofocusing Airy vortex beams in free space” (Manuscript ID: photonics- 1692472). We have studied the comments carefully and made corrections which we hope to meet with your approval. The revised portions are marked in red in the manuscript. The main corrections in the manuscript and the responses to the comments are as follows.

We appreciate reviewer’ s warm work earnestly.

Sincerely,

Xu Yan

Author Response File: Author Response.docx

Reviewer 2 Report

The manuscript addresses a new feasible method to control the phase structure of vortex beams, and promises potential applications in the OAM-based free space optical communication system. The authors base their predictions on a computer simulation of the complex amplitude of autofocusing Airy vortex beams, which they proposed without strong justification. I will be able to give any recommendations about publication of the manuscript only after a detailed discussion of my comments

 

1. Since when does the energy flux propagate in a spiral in free space?The article begins with such a controversial statement.

 

2. The OAM cannot form an orthogonal basis. This statement is false. The basis forms a closed orthogonal set of functions of several variables provided that certain requirements are fulfilled. At least, the authors confuse the basic concepts of physics and math. The chosen representation of complex vector fields in terms of the OAM is below any criticism.

 

3. The problem statement is completely incomprehensible.In the last paragraph of Introduction, the authors simultaneously talk about beams with nearly TM polarization and a wave front with optical vortices.The constant phase surface describes exclusively scalar fields, i.e.polarization components.Such formulations of the research problem cause bewilderment of the reader.

 

4. Missing the reference to Eq. (1). The authors forgot to substantiate whether Eq.(1) with control parameter m satisfies the paraxial wave equation?

 

6. Explain the phrase “…the radial polarization state change frequency of the light field increases with the increase of m”

7   Before we talk about trajectories on the Poincare sphere, we should at least explain this and provide an explanation with references

 

 

8  I have a bad idea what the authors mean by the terms “the vortex splitting in free space”. Generally speaking, a simple vortex beam is scattered in a turbulent medium into a wide 3D spectrum of vortex modes. This spectrum can hardly be represented through Airy beams. Most likely, Laguerre-Gauss modes are a more suitable basis. Moreover, the secondary modes are characterized by both amplitudes and phases. Therefore, to justify the proposed approach, it is necessary to use a more serious mathematical justification.

 

Author Response

Dear Reviewer，

Thank you for your comments concerning our manuscript entitled: “Mitigating vortex splitting by controlling wavefront isophase line curvature of vector autofocusing Airy vortex beams in free space” (Manuscript ID: photonics- 1692472). We have studied the comments carefully and made corrections which we hope to meet with your approval. The revised portions are marked in red in the manuscript. The main corrections in the manuscript and the responses to the comments are as follows.

We appreciate reviewer’ s warm work earnestly.

Sincerely,

Xu Yan

Author Response File: Author Response.docx

Reviewer 3 Report

In the submitted manuscript, the Authors present an analysis of vortex modes with the aim of reducing the vortex splitting effect in turbulent media and, thus, improving the stability of the modes. The method is well presented and some numerical simulations confirm the effectiveness of the proposed approach. Before possible publication, I suggest only the following minor edits:

• I would suggest adding a more detailed discussion about the effects of the reduction of the vortex splitting rate, reported in Table I, and the typical application of vortex modes in communication systems. In other word, the amount of reduction reported in Table I is enough in typical applicative scenarios?
• Figures should be inserted after being cited in the text.

Author Response

Dear Reviewer，

Thank you for your comments concerning our manuscript entitled: “Mitigating vortex splitting by controlling wavefront isophase line curvature of vector autofocusing Airy vortex beams in free space” (Manuscript ID: photonics- 1692472). We have studied the comments carefully and made corrections which we hope to meet with your approval. The revised portions are marked in red in the manuscript. The main corrections in the manuscript and the responses to the comments are as follows.

We appreciate reviewer’ s warm work earnestly.

Sincerely,

Xu Yan

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

The authors have taken into account all my comments, and I am inclined to recommend the article for publication