An Erbium-Doped Fiber Source with Near-Gaussian-Shaped Spectrum Based on Double-Stage Energy Matching and LPFGs
Round 1
Reviewer 1 Report
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Author Response
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Reviewer 2 Report
In this work, the authors proposed a near-Gaussian spectrum Erbium-doped fiber source with high output power and strong stability. The results seem interesting considering the wide applicability of Erbium-doped fiber sources. I think that this work could be acceptable for publication, provided that the issues below are properly addressed in the paper.
1. There are several grammatical errors in the text that need to be corrected. For example, there are two "The" in the first line of the second part.
2. In Figure 2, a space is required between the value and the unit.
3. Several recent reports on erbium-doped fiber sources need to be cited, such as DOI10.1002/lpor.201900367;
Author Response
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Reviewer 3 Report
Results on the review of the draft “An Erbium-doped fiber source with near Gaussian-shaped spectrum based on double-stage energy matching and LPFGs”
The study about An Erbium-doped fiber source with near Gaussian-shaped spectrum consists of only a single peak based on the double-stage energy matching and LPFGs. The study carried out shows results on an experimental arrangement consisting of two sections of erbium-doped fiber, which are pumped with two pump lasers and at the output, there are two long-period fiber gratings. The study is made from a scan of the powers of the pump lasers and because of this and the interaction of the light generated, a Gaussian beam can be obtained at the output of the fiber gratings. The results obtained are shown by figures where the output powers, optical spectrum variation, transmission at a certain wavelength, average wavelength, and other analyses that show results that prove the phenomenon are compared. However, after the results shown, I have the following questions and comments:
1. In the introduction, the authors mention that nobody has reported an Erbium-doped fiber source with single-peak spectra under variable pump power using conventional pump wavelength at 980 nm band. Then, authors are reporting something not reported before, but it is mandatory to explain what problem is solved with these findings.
2. In the introduction section, I would like to mention a couple of references that contribute in the sense of the state of the art in the results on the non-linear behavior of the erbium-doped fiber, the references are the following and could be added in line 38, and are the next:
https://doi.org/10.3390/math10173140
https://doi.org/10.1016/j.jfranklin.2017.08.052
3. About the lengths of the EDF, why to use such lengths? What could happen if the lengths are equal or if one length is an integer multiple of the other? Please explain and clarify.
4. On line 81, repeated words “were manufactured” appear.
5. Could the authors please add a figure explaining the process of the ASE generation between the different erbium energy levels for the 1530nm and 1560 nm radiation? The last could contribute to a better explanation of the experimental results.
6. It is not clear to me, how the first stage of the EDF will generate 1530 nm, if the wavelength of the erbium emission is around 1550nm, why the authors, using the same EDF type, can assure that one wavelength will be different of the other?
7. For figure 3, if the sum of the LPFGs gives a better transmission for 1550 nm, why the Gaussian response has 1560 nm? Please explain.
8. In the section on conclusions, in addition to mentioning what was found, the authors must clearly explain the benefits of the results shown, as well as the problem solved, applications, and possible future work.
After clarifying and making the requested corrections, I may consider accepting this paper.
Author Response
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Author Response File: Author Response.pdf
Round 2
Reviewer 3 Report
I consider that the authors have made the requested corrections, as well as answers to my doubts. For my part the paper can be accepted.
