Characterizing the Thermally Grown Oxide in Thermal Barrier Coating by Terahertz Time Domain Spectroscopy

Round 1

Reviewer 1 Report

The authors describe an interesting approach to estimate the optical properties and thickness of thin films. 

The work is more or less well organized however poorly described.  I did not find any relationship between the thickness of the layers and the equations shown here. Moreover, I also didn't see any relationship between "the x-axis" (of figures) and the equations. 

For me was not clear how the signal was simulated based on these equations. The authors should develop further the way how the simulations were performed.

The whole work is focused on this fitting approach then is mandatory to introduce properly how the simulations were carried out, and what is the impact of the film thickness on the signal.  

It would be interesting to see how the optical constants change (or not) by fixing the thickness and vice versa. Moreover, the error of the fit is not discussed. 

 

 

Author Response

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Reviewer 2 Report

Comments for author File: Comments.pdf

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Round 2

Reviewer 1 Report

the authors answered almost everything. the only reminder question is how robust is the fit to each parameter. 

That means What is the value of the optical properties if you fix the thickness using SEM values? (i.e., you kept constant the thickness and just varied the optical properties).

 

 

Author Response

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Reviewer 2 Report

The paper in this form can be accepted.

Author Response

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Author Response File: Author Response.docx