Plasmonic Vortices: A Promising Tool Utilizing Plasmonic Orbital Angular Momentum
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors
This article provides a comprehensive review of the generation, manipulation, and applications of plasmonic vortex beams. Firstly, the article systematically summarizes the mechanisms and methods for generating and controlling plasmonic vortex beams, reflecting the breadth of the content. In terms of generation mechanisms, it covers various experimental approaches, such as designs based on different metal materials, surface microstructures, and different excitation methods for plasmon polaritons. Regarding manipulation, the discussion likely includes techniques such as laser sources, optical field modulators, and surface structuring, which highlights the technological diversity in this field. The article not only organizes the fundamental theories of plasmonic vortex beams but also emphasizes their potential in practical applications. For instance, the local enhancement effects of surface plasmonics in areas such as tip-enhanced Raman spectroscopy, chiral detection, and micro/nano manipulation, provide readers with a panoramic view of interdisciplinary applications. The prospects of plasmonic vortex beams encompass multiple frontier fields, including micro/nanotechnology and optical manipulation. However, there are some problems in the manuscript that require major revision. Below are some comments:
(1) Based on previous research, the authors list some unresolved technical challenges related to the detection and application of plasmonic vortex beams. For example, how can the propagation efficiency of plasmonic vortex beams be improved, and how can the generation and transmission process of vortex beams be optimized? By discussing future technological bottlenecks and challenges, the author could provide readers with motivation and inspiration for further research.
(2) The authors should carefully check for formatting issues, such as the three-time occurrence of Fig. 3(c) in the text.
(3) For the section 4.6, which discusses Electron Beam Shaping, you may refer to the following reference 'Huo PC, Yu RX, Liu MZ et al. Tailoring electron vortex beams with customizable intensity patterns by electron diffraction holography. Opto-Electron Adv 7, 230184 (2024).
(4) In Section 4.2, under 'Chirality Detection,' the reference 'Brullot, W.; Vanbel, M.K.; Swusten, T.; Verbiest, T. Resolving Enantiomers Using the Optical Angular Momentum of Twisted Light. Science Advances 2016, 2, e1501349' seems somewhat inappropriate. The article is a review of near-field surface plasmonic vortex beams, whereas the referenced work involves the use of far-field vortex light to illuminate metallic particles in the near field to achieve local enhancement for chiral detection.
(5) Some important references are missing. For instance, see Science Advances, 2015, 1(9): e1500396.
Author Response
Comments 1: [ Based on previous research, the authors list some unresolved technical challenges related to the detection and application of plasmonic vortex beams. For example, how can the propagation efficiency of plasmonic vortex beams be improved, and how can the generation and transmission process of vortex beams be optimized? By discussing future technological bottlenecks and challenges, the author could provide readers with motivation and inspiration for further research.]
Response 1: [ The part has been included and modified in the conclusion section.]
Comments 2: [ The authors should carefully check for formatting issues, such as the three-time occurrence of Fig. 3(c) in the text.]
Response 2: [ Thank you for pointing that out. The originally submitted document was a Word format, which did not have this issue. However, after checking the PDF version-likely generated by the journal-the problem does exist. I also met the same problem too when I did format conversion. The layout problem during the format conversion has now been fixed.]
Comments 3: [ For the section 4.6, which discusses Electron Beam Shaping, you may refer to the following reference 'Huo PC, Yu RX, Liu MZ et al. Tailoring electron vortex beams with customizable intensity patterns by electron diffraction holography. Opto-Electron Adv 7, 230184 (2024).]
Response 3: [ This reference has been added and the related content has been modified accordingly and updated in the manuscript.]
Comments 4: [ In Section 4.2, under 'Chirality Detection,' the reference 'Brullot, W.; Vanbel, M.K.; Swusten, T.; Verbiest, T. Resolving Enantiomers Using the Optical Angular Momentum of Twisted Light. Science Advances 2016, 2, e1501349' seems somewhat inappropriate. The article is a review of near-field surface plasmonic vortex beams, whereas the referenced work involves the use of far-field vortex light to illuminate metallic particles in the near field to achieve local enhancement for chiral detection.]
Response 4: [ As stated in the manuscript: “These findings suggest that nanoplasmonic vortices, with their enhanced fields, could potentially discriminate enantiomers via high-order transition moments.” We have simply highlighted this as a prospective direction and do not currently have additional directly proved references. ]
Comments 5: [ Some important references are missing. For instance, see Science Advances, 2015, 1(9): e1500396.]
Response 5: [ It has been added in the manuscript as you said. Thank you for all your comments! Please check the highlighted manuscript.]
Author Response File: 
Author Response.docx
Reviewer 2 Report
Comments and Suggestions for Authors
This article reviews these studies in three key areas: a) the generation and manipulation of PVs, b) the characterization of PVs, and c) the application of PVs. We believe that PVs represent a promising tool of plasmonic OAM for both fundamental research and practical applications and hold a great potential for thefuture with continued dedicated efforts. There are some questions about the presented work. I would recommend publication of this paper if the authors solve the following comments in a revised version.
1. Mentioned in the article :” plasmon-enhanced Raman and fluorescence, surface plasmons are crucial as they can highly confine and significantly enhance electric fields. This has led to greatly improved detection sensitivity and has paved the way for numerous applications since the discovery of the effect”. The author should cite more references to prove it.
2. The single bracket above figure 3b is deleted.
3. The layout of the part in Figure 3 is confused, and the corresponding part should be illustrated or explained.
4. In part 2.3 of the paper, the author should briefly explain the mechanism of spatiotemporal dynamics/modulation of plasmonic vortices, not just describe its development history.
5. The author should briefly describe the application and development prospect of PVs.
6. Quotes in the text should be specific, such as :” Zhang et al. proposed a more complex coaxial AS structure, and their simulation results indicated improved coupling efficiency as a circular polarization analyzer [66].” How much coupling efficiency is specifically improved, the author should give.
7. The quotation in part 4.2 is wrong.
8. Check the language and variety of the text carefully.
Author Response
Comments 1: [ Mentioned in the article :” plasmon-enhanced Raman and fluorescence, surface plasmons are crucial as they can highly confine and significantly enhance electric fields. This has led to greatly improved detection sensitivity and has paved the way for numerous applications since the discovery of the effect”. The author should cite more references to prove it.]
Response 1: [ More references have been added to support this point.]
Comments 2: [ The single bracket above figure 3b is deleted.]
Response 2: [ Thank you for pointing that out. We originally submitted the document in Word format, which did not have this issue. However, after checking the PDF version-likely generated by the journal-the problem does exist. I also met the same problem too when I did format conversion. The layout problem during the format conversion has now been fixed.]
Comments 3: [ The layout of the part in Figure 3 is confused, and the corresponding part should be illustrated or explained.]
Response 3: [ Thank you for pointing that out. We originally submitted the document in Word format, which did not have this issue. However, after checking the PDF version-likely generated by the journal-the problem does exist. I also met the same problem too when I did format conversion. The layout problem during the format conversion has now been fixed.]
Comments 4: [In part 3 of the paper, the author should briefly explain the mechanism of spatiotemporal dynamics/modulation of plasmonic vortices, not just describe its development history.]
Response 4: [ The modification has been made in the manuscript.]
Comments 5: [ The author should briefly describe the application and development prospect of PVs.]
Response 5: [ The modification has been made and included it in the conclusion section.]
Comments 6: [ Quotes in the text should be specific, such as :” Zhang et al. proposed a more complex coaxial AS structure, and their simulation results indicated improved coupling efficiency as a circular polarization analyzer [66].” How much coupling efficiency is specifically improved, the author should give.]
Response 6: [ The referenced paper doesn’t explicitly mention it either, but they do illustrate it in the figure.]
Comments 7: [ The quotation in part 2 is wrong. ]
Response 7: [ As stated in the manuscript: “These findings suggest that nanoplasmonic vortices, with their enhanced fields, could potentially discriminate enantiomers via high-order transition moments.” We have simply highlighted this as a prospective direction and do not currently have additional directly proved references.]
Comments 8: [ Check the language and variety of the text carefully.]
Response 8: [ Some issues have been fixed.]
Thank you very much for all comments! Please check the updated and highlighted manuscript.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
Comments and Suggestions for Authors
The revised manuscript has addressed my concerns.
