PONE-D-24-46249Luminescence Properties of Ge and Ge-Si Structures on Silicon-Based MicrocavitiesPLOS ONE

Dear Dr. Zhao,

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Mallikarjuna Reddy Kesama, Ph.D.

Academic Editor

PLOS ONE

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Additional Editor Comments:

This manuscript presents a detailed investigation into the luminescence properties of Ge and Ge-Si structures on silicon-based microcavities, employing innovative methods like laser etching and pulsed laser deposition (PLD). The study is comprehensive, with robust experimental design and clear data presentation, highlighting key findings such as dual luminescence peaks at 700 nm and 940 nm. However, the manuscript would benefit from a more concise introduction that sharpens its focus and highlights the novelty of the research. The results and discussion sections could be strengthened by integrating comparisons with existing literature and providing deeper insights into the mechanisms driving the observed luminescence. Additionally, improvements in figure clarity, language precision, and reference formatting are necessary to enhance readability and impact. Overall, the research has significant implications for advancing silicon-based luminescent materials, and addressing these issues will further align the manuscript with the expectations of a high-impact audience.

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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: Partly

Reviewer #2: Partly

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

Reviewer #1: N/A

Reviewer #2: N/A

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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 manuscript titled “Luminescence Properties of Ge and Ge-Si Structures on Silicon-Based Microcavities” is systematic and well written. The laser etching, subsequentially PLD process Ge and Si-Ge growth is novel technique. However, the argument of Luminescence significance in the report is not confirmed. It is rather micro-Raman analysis of SiGe nanocrystal. Authors tried to establish the strained SiGe nanolayers optical significance on Ge coated microcavities. Without annealing, the grains orientation shown by SEM and XRD analysis are realized polycrystalline properties. Generally, high temperature there is a possibility of Si diffusion and deteriorates crystalline properties. Moreover, high energy LASER application and greater oxygen contamination can make it polycrystalline. The micro–Raman TO broader peak seems to display it. Is there any evidence to retain its crystallinity? As grown SiGe nanostructure clustering is less dominant while Si XRD broader peak is dominant. The annealing time dependent XRD and micro–Raman TO peaks recognized that the nanocrystalline quality of Ge-O is gradually improved until certain annealing time afterwards it deteriorates again. The strain effect associated to the annealing time dependent crystalline quality that is expected to eventually improve the nano-crystalline properties. The annealed sample both Ge-O nanocrystal and Si (400) crystalline XRD peaks are dominant in which % of Si atom is decreased due to dominance of O atoms in the composition. The annealed SiGe coated microcavity both XRD and micro-Raman distinctive TO peaks for Ge-O and Si-Si bond are shown prominent. It is also characterized as annealing time dependent modulation of SiGe crystallinity. Either photo or electroluminescence can predominantly demonstrate the luminescence attributes of any crystalline size of semiconductors. To attributes SiGe nanostructure novel photonics, the dark current associated rectification ratio is most validated electrical characterization.

Reviewer #2: Presentation issues.

Section 2.1 Experimental Equipment

The authors do not give information on the type and brand (series) of the X-ray spectrometer used.

The same applies to the X-ray diffractometer.

The series of the Renishaw spectrometers is not presented either.

Globally.

The authors do not use Raman spectroscopy, but only photoluminescence one. RENISHAW Raman spectrometers usually enable studying both Raman scattering and photoluminescence using an appropriate channel.

In the text, abstract and figure captions, the terms such as Raman spectroscopy, Raman spectrum or Raman spectra, etc. must be replace with photoluminescence spectroscopy, photoluminescence spectrum (spectra), etc.

Pages 2 and 5. “Error! Reference source not found”

Figure 1. The inscription at the scale mark on the panel (a) is too small: it is difficult to see what is written.

Figures 2. The authors should indicate the mode of imaging on panels (a) and (b) or in the caption. Are the images secondary electron (SE) or backscattered electron (BSE) ones?

The authors should also reformulate the caption. Panel (c) does not show an image.

Besides, the table in the insert gives “quality percentage”. Maybe the authors mean percentage content. Is this atomic or weight percentage?

Further, the axes do not show titles and units of measurements. I can see that the energy of quantum in keV is given on the x-axis and the emission intensity is given on the y-axes (in some units, perhaps in pulse/sec/eV, as it is typical for AZtec (Oxford Instruments) EDX spectrometers).

The same applies to Figures 6 and 7.

Figures 3, 4 and 9. The units for the 2θ axes are not shown; I can see that they are degrees, yet the authors must indicate the units of measurements for all the axes.

In addition, there are no titles and units of measurements at the y-axes.

What diffractometer did the authors use? It should be indicated in Section 2.1 as well as the X-ray source (wavelength).

Finally, the authors did not indicate the temperature at which the luminescence was measured.

Text

Page 3, Section 2.2, paragraph 1. The surface cleaning process, including purity of cleaning agents, should be described in more details.

Obtaining of a clean Si surface is a key process for preparing a perfect structure.

Are the authors sure that the resultant Si surface was sufficiently clean after the described treatment and did not introduce uncontrolled impurities into the prepared structures?

What were the conditions in the chamber when etching cavities in Si?

“…spectrum of the sample is displayed in Figure 1(b), featuring a characteristic luminescence peak at 700 nm attributed to the silicon-based microcavity.” What are the rest peaks in the PL spectrum? As far as I can see, the sharp peak at ~547 nm is assigned to the TO phonon in crystalline Si (Raman shift ~ 520 1/cm), isn't it? The peak at 540 nm is 2TA in c-Si (Raman shift ~300 1/cm) and that at ~563 nm should be 2TO in c-Si (Raman shift ~1040 1/cm).

Are peaks related to SiO2 seen in the spectra? The Raman scattering bands associated with vibrations of the Si–O bonds in SiO2 might appear around 560 nm (Raman shift from ~800 to ~1200 1/cm) if silicon dioxide is present in the structure [DOI: 10.2138/am.2006.2075].

Page 4, paragraph 1. What was the gas composition of the atmosphere in the deposition chamber during the process? Was it clean enough in the chamber for the process to be conducted in correct conditions? Did the authors use some high-purity gases in the chamber? To what pressure was the chamber evacuated before the process?

Section 3.1, paragraph 1. “Figure 1(a) shows…” Figure 2(a)...

Page 5. Could the authors comment on the peaks at ~57° and ~75° in Figure 3(a) and the width of the band at 69°? If the former is GeO2, why did Ge oxidize when deposited? This should be briefly discussed in the text.

“The peaks at 31° and 69° correspond to the Si (200) and Si (400) crystal planes, indicating the presence of Ge and Si elements in the microcavity samples on the silicon substrate.”

Why Si peaks indicate the presence of Ge? Please, formulate the statement clearer.

Page 6. “Peaks at 31° and 69° correspond to the Si (200) and Si (400) crystal faces, indicating the presence of Ge and Si elements in the microcavity samples deposited on the silicon substrate, with possible incorporation of Ge elements.”

Again, why Si peaks indicate the presence of Ge? Please, formulate the statement clearer.

As far as I understand from Figure 4, initially, the authors see a Si(200) peak from the substrate, Si(400) from nanocrystals, two peaks from Ge and a reflection from GeO2(210) and some undiscussed reflection. After annealing for 10 min., they see the same pattern; in 20 min., the pattern is nearly the same, yet some new undiscussed reflections appear; in 30 min., the pattern mainly remains, yet Si(200) seems to have decreased, Ge (220) and (210) increased, Si (400) increased, some unidentified reflexes disappeared, whilst some intensified.

In 40 min., a strong narrow Si(400) reflex appears (poly-Si forms?). Ge(113) appears.

In 50 min., Si(400) (poly-Si?) go on growing. GeO2 decays.

In an hour, the reflexes weaken. (Why?)

Could the authors comment on this process by discussing what was happening to the Si, Ge and GeO2 during annealing.

Page 7. “…but with an additional sharp peak at this wavelength.”

This line is seen on panel (b).

“Thus, the sharp peak at 700 nm is due to localized luminescence from Ge-O bonds within these clusters.”

This statement does not seem entirely substantiated. The authors should give a justification for it.

What the authors mean when writing about the luminescence of the Ge–O bond? Do the authors mean the Raman band? GeO2 is transparent for the 532-nm laser.

Please, clarify this paragraph regarding the origin of the line peaking at 700 nm!

Figure 6. Perhaps, oxygen came on the surface due to film oxidation in the atmosphere during its moving to SEM. Otherwise, it is present in the SEM chamber. The treatment at 1000°C for 40 min should completely deoxidize the structure.

Figure 8. What is unannealing? Unannealed.

Section 3.3. “For the prepared germanium-coated silicon-based microcavity samples, PLD was used to deposit silicon onto a silicon target, followed by a layer of silicon structured over the germanium, creating a Ge-Si bilayer structure on the microcavity samples.”

The phrase is unclear. Please, reformulate it.

Section 3.4. The authors should explain where oxygen appears from in their experiment on annealing. Does the deposition chamber contain a lot of O2 gas in its atmosphere? Otherwise, the structure should deoxidize at such a high temperature. A few minutes should be enough to remove oxygen completely from the structure in vacuum or oxygen-free residual atmosphere.

My conclusion.

The manuscript may be considered for publication only after the authors have resolved all of the above issues.

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Reviewer #1: Yes:  Bablu Kumar Ghosh

Reviewer #2: No

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PONE-D-24-46249R1Luminescence Properties of Ge and Ge-Si Structures on Silicon-Based MicrocavitiesPLOS ONE

Dear Dr. Zhao,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Please submit your revised manuscript by Feb 24 2025 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org . When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

• A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.
• A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
• An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols . Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols .

We look forward to receiving your revised manuscript.

Kind regards,

Mallikarjuna Reddy Kesama, Ph.D.

Academic Editor

PLOS ONE

Journal Requirements:

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

Additional Editor Comments:

The manuscript needs a thorough revision to address several issues related to typos, missing words, proper capitalization, and sentence structure for better clarity and readability.

Specific comments for figures and presentation:

General formatting: Ensure all graphs have the same font size and avoid using bold fonts in SEM images. Use a white background for all figures. Remove unnecessary boxes around titles (e.g., "unannealed" or "annealing at different timings").

Figure-specific Comments:

Figure 2c: Missing information for the x-axis (Energy in KeV) and y-axis (Intensity(a.u.)).

Figure 3a & 3b: Y-axis information is missing for Figure 3a. the font style differs between Figures 3a and 3b when compared to Figure 2. Maintain uniformity.

Figure 4: Clearly label the y-axis (e.g., Intensity (a.u.)). The inset in figure 4e is unclear and needs to be replotted for better visibility.

Figure 5a: The line thickness is inconsistent compared to other lines in the figure. Ensure uniformity.

Figures 6a, 6b, and 6c: Replace bold fonts with normal fonts and use a white background.

Figure 7: Use normal font for labels (a, b, c). X-axis and y-axis information is missing.

Figure 8a: Y-axis information is missing.

Figure 9: Y-axis information is missing in all parts.

Figure 11: Revise this figure to match the updated standards.

Axis Intervals: Across Figures 1 to 11, the y-axis has too many interval points. Use larger intervals to make the data presentation clearer.

Reviewer comments:

Address all reviewer comments thoroughly.

Overall Presentation: The current presentation of data gives the impression of inexperience in publishing articles. Revise figures and text to improve the quality and professionalism of the manuscript.

Kindly address these suggestions and ensure all corrections are made in both text and figures.

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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

Reviewer #2: (No Response)

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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

Reviewer #2: Yes

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

Reviewer #1: N/A

Reviewer #2: N/A

**********

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

Reviewer #2: Yes

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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

Reviewer #2: Yes

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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 manuscript wording has been revised. Anyway, the Raman spectroscopy is not photoluminescence. Please address the real methodology and marked it properly. The high spectral resolution of a Raman spectrometer can be useful for PL spectroscopy, especially when the emission spectra have narrow bands or lines. Though it is not mentioned properly.

Reviewer #2: 1) What do the authors mean when writing “Characterization images…”? Maybe, the authors could just use “characterization” in the captions?

2) The word “photoluminescence” should not be capitalized unless it begins a sentence.

Please check your manuscript carefully for typos!

3)

170 “In this experiment,

171 silicon wafers were soaked in a solution of 95% concentration of

172 ethanol and acetone mixed 1:1 for five minutes to remove surface

173 organic matter, then submerged in deionized water and cleaned in an

174 ultrasonic cleaner for 15 min.”

Please, indicate the purity of the components.

4)

166 “Photoluminescence (PL) spectra were measured at

167 room”

… room temperature.

5)

205 “The deposited samples were then placed in a

206 tube furnace where they were annealed at 1000°C for varying

207 durations to study the luminescent properties of the samples with

208 different deposited elements and annealing times.”

The pressure and the atmosphere composition should be presented in the text. The pressure in the deposition chamber before the process is also absent in the text.

6)

234 “Peaks at 27° and 45° correspond to the Ge (110) and

235 Ge (220) crystal planes, respectively, and are sharp and narrow,

236 indicating high crystallinity. The peaks at 31° and 69° correspond to

237 the Si (200) and Si (400) crystal planes. Indicating the presence of

238 Ge and Si elements in the microcavity samples on the silicon

239 substrate.”

From my point of view, the statement in the text has become even less comprehensible.

The sentence written in the response to my comment is much clearer: “The XRD pattern reveals the coexistence of Ge (110) and Ge (220) crystal planes, as well as Si (200) and Si (400) crystal planes on the surface of the silicon-based microcavity. This indicates the presence of both Ge and Si elements in the microcavity samples deposited on silicon substrates.”

Sorry, I cannot understand the remark 此部分仅是回复。Google translates it as “This is a very important part of our work.”

7)

239 The 57° and 75° germanium dioxide peaks may result

240 from low peak intensities due to a small amount of oxidation on the

241 surface of the sample after preparation or during testing.

The phrase is poorly formulated. The phrase “a small amount of oxidation” is unclear.

8)

248 based clusters at the edge of the microcavityError! Reference source not found..

From the authors’ response.

9) “Could the authors comment on this process by discussing what was happening to the Si, Ge and

GeO2 during annealing.

My response�As the annealing time varies, the gradual improvement in the quality of Ge-O nanocrystals

can be observed through the TO peak of XRD and Raman spectroscopy, until a certain annealing time is

reached where the Ge-O cluster structure is disrupted. The strain effect associated with annealing time is

expected to ultimately enhance the properties of the nanocrystals. The XRD peaks of both germanium

oxide nanocrystals and silicon (400) crystals dominate in the annealed samples, with the percentage of

silicon atoms decreased due to the dominance of oxygen atoms in the composition.此部分仅是回复。”

I recommend including this discussion in the manuscript.

10) “Please, clarify this paragraph regarding the origin of the line peaking at 700 nm!

My response�A group has employed a quantum dot confinement model to calculate the energy gap

structure of germanium oxide nanocrystal clusters, and utilized the Monte Carlo method to simulate the

PL spectrum and the corresponding size distribution of the germanium oxide nanocrystal clusters. The

calculated results are in agreement with our experimental findings, leading us to analyze that this is due

to the specific luminescent peaks exhibited by small-sized Ge-O clusters formed through the combination

of small-sized Ge and O.此部分仅是回复。”

In my opinion, this should be written in the text. Otherwise, the statements are quite speculative.

In addition, it is advisable to present the simulation results as a supporting material.

11) “15. Figure 6. Perhaps, oxygen came on the surface due to film oxidation in the atmosphere during

its moving to SEM. Otherwise, it is present in the SEM chamber. The treatment at 1000°C for 40

min should completely deoxidize the structure.

My response�The sample surface is populated with many small-sized germanium crystal clusters. When

the sample is processed under annealing conditions, the germanium crystals on the surface react with

oxygen atoms. After the oxygen atoms diffuse into the germanium layer, they coalesce into Ge-O clusters

above the oxide layer. However, annealing for a duration longer than a certain threshold can disrupt the

cluster structure of Ge-O. 此部分仅是回复。”

Unfortunately, the description of the annealing conditions is absent in the text. They should be presented.

12) “18. Section 3.4. The authors should explain where oxygen appears from in their experiment on

annealing. Does the deposition chamber contain a lot of O2 gas in its atmosphere? Otherwise, the

structure should deoxidize at such a high temperature. A few minutes should be enough to remove

oxygen completely from the structure in vacuum or oxygen-free residual atmosphere.

My response�The deposition process is carried out under vacuum conditions, while the annealing process

is conducted in an atmospheric environment. The source of oxygen during annealing is the oxygen

present in the atmosphere, which reacts with the surface Ge under high temperature to form a cluster

structure of Ge-O.此部分是回复.”

This should be stated in the text.

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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

Reviewer #2: No

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Attachments

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Submitted filename: Comments R1.pdf

PONE-D-24-46249R2Luminescence Properties of Ge and Ge-Si Structures on Silicon-Based MicrocavitiesPLOS ONE

Dear Dr. Zhao,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Please submit your revised manuscript by Mar 28 2025 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org . When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

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Kind regards,

Mallikarjuna Reddy Kesama, Ph.D.

Academic Editor

PLOS ONE

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Luminescence Properties of Ge and Ge-Si Structures on Silicon-Based Microcavities

PONE-D-24-46249R3

Dear Dr. Shihua Zhao,

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,

Mallikarjuna Reddy Kesama, Ph.D.

Academic Editor

PLOS ONE

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

Reviewer #2: 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

Reviewer #2: (No Response)

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

Reviewer #1: Yes

Reviewer #2: (No Response)

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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

Reviewer #2: (No Response)

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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: No

Reviewer #2: (No Response)

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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 addressed all issues relating to publishing the manuscript. Now the paper is ready for publishing.

Reviewer #2: The authors took into account the reviewer’s comments and revised the manuscript accordingly.

I advise publishing the revised manuscript.

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Reviewer #1: No

Reviewer #2: No

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