To address the questions to the authors:

@Q1: We are fine with the change to the recommended hyphenation, thanks!

@Q2: breaking down fractions in super/subscripts in eqns 6,7,9 is correct.

@Q3: Please replace "FWM" with "four wave mixing" (line 264 is the only place)

@Q4: According to our latest acknowledgement policy, we are supposed to add another institution. Therefore, please replace in lines 351/352 the sentence
"This work was supported...Singapore."
by
"This research is supported by the Research Centres of Excellence programme supported by the National Research Foundation (NRF) Singapore and the Ministry of Education, Singapore."
The first funding body was identified corrrectly in the proof. The second institution has a fundref entry http://dx.doi.org/10.13039/501100001381 of this helps.

@Q5: All existing links to doi in the references appear to be correct, we did
not find one for references without a link.

@Q6: The publication year of ref. 30 is 2017, the proof is correct.

Additional changes:

The usage of an ellipsis with commas in lines 71 and 74 on page 1 seems
strange, as this suggests a discrete set of numbers, while we intend to
indicate a continuous range. We could not identify a specific directive in the
style guide for this supposedly common case, but recommend either to use "0.1
... 1 THz" and "0.1 ... 10 km" (ellipsis without commas), or "0.1 to 1
THz" and "0.1 to 10 km" (range explicitly indicated by the word "to"),
respectively, consistent with the range description in line 236/237.