PONE-D-21-35833Large Electromagnetic Field Enhancement in Plasmonic Nanoellipse for Tunable Spaser Based ApplicationsPLOS ONE

Dear Dr. Waqas Farooq,

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PLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

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3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

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4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

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5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: The authors theoretically demonstrated a class of plasmonic coupled elliptical nanostructure for achieving a spaser or a nanolaser with high intensity. Technically, the authors employ the numerical methods with apparent authority and the results seem valid. This work is interesting for the readership and deserve publication after major revision. This work will be more impactful if the authors address the following comments.

1. Figs. 2-9 (c) and (d) are blurred. Please replace them as the clear ones.

2. The references used in introduction section should be improved. It is written in abstract section that “Giant localized field enhancement and high LSPR values enable the proposed model to be highly appealing for sensing applications, surface enhanced Raman spectroscopy”. To be beneficial for the readers to enrich the mechanism and background of plasmonic sensor and surface enhanced Raman spectroscopy, the authors should mention the other approaches of plasmonic sensor, i.e., Nanomaterials, 10, 1399 (2021), J Phys D: Appl Phys, 54, 115301(2021)), Results in Physics, 15, 102567(2019) and Nanomaterials, 9,1691 (2019), and for surface enhanced Raman spectroscopy (i.e., Optics Express, 21, 24460 (2013)).

Reviewer #2: The authors reported a class of plasmonic coupled elliptical nanostructure for achieving a spaser or a nanolaser with high intensity. The FEM calculations showed that the LSPR peaks and the local field intensity or near field enhancement (NFE) of the active nanosystem can be amplified to higher values by introducing symmetry-breaking techniques in the proposed ellipse and its variants. Giant localized field enhancement and high LSPR values enable the proposed model to be highly appealing for sensing applications, surface enhanced Raman spectroscopy, and much more. The research is significant, the amount of data is large, and the contrast for characteristic parameters of different-type nano-structures is clear. However, before possible publication, some of the listed points should be explained and revised for further improving the manuscript.

1. Authors theoretically investigated a class of plasmonic coupled elliptical nanostructure for achieving spaser, but the shape of SBNE structures were unusual and whether they can be prepared for practical application?

2. Why the structure type with maximum NFE for Elliptical nano-structures for the x polarization was SBLCNET, but the structure type with maximum NFE for Elliptical nano-structures for the y polarization was LCNEQ rather than SBLCNET?

3. The calculated results should be supported by some experimental data through experimental measurement or experimental results from literatures.

4. How does the performances (such as NFE) of the structures in this work when compared with that in literatures.

5. There were too many abbreviations, so it is recommended to put them in a table.

6. The table note for Table 3 should be Table 2.

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Reviewer #1: No

Reviewer #2: No

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Large Electromagnetic Field Enhancement in Plasmonic Nanoellipse for Tunable Spaser Based Applications

PONE-D-21-35833R1

Dear Dr. Farooq,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

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If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

Yuan-Fong Chou Chau

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: The authors have revised their mauscript according to my comments. This manuscript can now be accepted for publication.

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7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No