Nanocrystalline Yb:YAG-Doped Silica Glass with Good Transmittance and Significant Spectral Performance Enhancements
, Hui Zhang 1, Yujie Lu 1, Shikai Wang 1,*, Chunlei Yu 1,2,* and Lili Hu 1,2,*Round 1
Reviewer 1 Report
The manuscript "Nanocrystalline Yb:YAG doped silica glass with good transmittance and significant spectral performance enhancements " presents interesting experiment results of fabricated glasses. The presented data and discussion are interesting. However, some issues should be explained:
- What is the scale of EPMA surface scans presented in Fig. 2, what is the dopants concentrations?
- "The XRD patterns of the YABS and YAS glass were almost identical and both showed amorphous glass structures" Please show the evidence of the crystal structure.
- What is the distribution of the large crystal presented in Fig. 4a?
- What are the excitation spectra of doped YABS and YAS glass?
- What is the double/single decay curve difference of YABS and YAS glasses?
- What is the application field of presented material in optical fibre technology? How to apply it in the optical fibre preform (it is well known that in such a temperature range the crystalline structure of nanoparticles can be damaged)?
- The sol-gel methods often cause some impurities in the final host glass. What was the quality of fabricated glasses?
Author Response
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Author Response.docx
Reviewer 2 Report
This is a generally well written paper that deserves publication after some minor comments are addressed.
It is a bit surprising that vacuum sintering for 1h did not lead to the occurrence of some crystallization of a silica-rich phase. Please comment.
Why was BaO used as a nucleating agent, instead of an oxide of a high valence cation like Ti4+, Zr4+ or P5+?
Based on the very similar ionic radii of Y3+ and Yb3+, the preferential replacement of Y3+ by Yb3+ in the YAG phase was to be expected (see e.g. J. Ferreira et al., JSST 83 (2017) 436). Please comment.
The fast fluorescence decay of Yb3+ ions observed in the YABS materials with a value of ~ 30 micro-seconds could be due to the fact that the Yb3+ ions which replace Y3+ in the YAG phase become probably much more closely spaced than the Yb3+ ions in the GP and this clustering effect is expected to significantly reduce the emission lifetime. Please discuss.
Author Response
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Reviewer 3 Report
The paper with title: “Nanocrystalline Yb:YAG doped silica glass with good transmit- 2tance and significant spectral performance enhancements “ by Hehe Dong, Yinggang Chen, Jiao Yan, Qinling Zhou, Yue Cheng, Hui Zhang, Yujie Lu, Shikai Wang, Chunlei Yu and Lili Hu presents a beautiful current research focused on study perspective new generation hight-frequency laser materials. In the article, the authors managed to prepare and fully characterize the properties of a new functional material, i.e. silicate glass containing Yb: YAG nanocrystals with size 22 nm.
The scope of article is considerable. Clarity and ordering of the issue are very good. The presented article provides a very good overview of current knowledge about combination of silicate matrix and RE:YAG materials. I mean that article also reflect the focus of the journal. The manuscript is very well written in clear English, the number of citations is sufficient.
Finally, I think there is a great deal of honest experimental work behind these results, and I congratulate the authors on these results. I recommend the manuscript for publication after minor revision mentioned below.
Recommended minor revision:
line 76-92: In that paragraph, I recommend only a description of the preparation or analysis that is used in the article. In my opinion the description of the results is premature here and I recommend to omit it.
line 130-131: Table 1 – To the value of the refractive index, I recommend add the wavelength at which the value was determined.
line 158: Figure 2(b) - Which colour belongs directly to ytterbium?
line 179: “quadrilat- eral” change to quadrila-teral
line 191: GP acronym is missing an explanation
line 216: “respec- tively” change to respec- tively.
line 238: “inter-esting” change to intere-sting
line 295: It is not clear which relationship complies with these two laws. I also recommend not mentioning Figure 8 here - it seems confusing.
line 345: Conclusion
It is not entirely clear from the whole article where Yb3+ is located, whether in the glass phase or in nanoparticles. Figure 5 presents the result of the analysis just of one nanoparticle. I interesting for me if more than one of these analyses has been done with the same result? If so, I would recommend including them in the text of article. If the authors are more inclined to the fact that more Yb3+ is present in the glass phase, I wonder what mechanism could then explain the better luminescence properties of the nanocrystalline material? If you have such a hypothesis, it would be nice to include it in the article.
Author Response
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Round 2
Reviewer 1 Report
The manuscript can be accepted in the present form.
