Angular Quasi-Phase-Matching in Periodically Poled Uniaxial and Biaxial Crystals

Round 1

Reviewer 1 Report

This article described AQPM in uniaxial and biaxial crystals by introducing topologies and symmetries for second-order nonlinear optical interactions for frequency conversion. The periodically-poled crystals, 5%MgO:PPLN and PPRKTP, were utilized for verifying the calculated results. However, some aspects need to be addressed. I would recommend that the manuscript gets published, after the authors address the following points:

 (1) In the section 5, the well-polished materials shaped as a sphere were introduced, authors should mention the reason briefly in the manuscript and how they are different to common wafers. Scrupulously, please illustrate why not choose the uniform diameter of 5%MgO:PPLN, 7%MgO:PPLN, and PPRKTP.

 (2) In Figure 7, the point B, explanatory chart, and chart numbers missed, which influence the analyses of results.

 (3) Please explain the reason for selection of λ_ω = 1550 nm as the fundamental wavelength for the experiment on nonlinear effective coefficient. Is there any specific reason for this selection?

 (4) Table 5 provides the description of accessible types of SHG interactions in a 7%MgO:PPLN with a grating period ∧ = 15 μm. As the higher percentage of MgO may provide larger the laser/surface/electrical damage threshold, please explain the reason for selection of 7%MgO:PPLN in this section.

 (5) The image resolution of Figures throughout the text should be upgraded. The chart numbers of Figures should be supplied. And the formula symbols need to be uniformed throughout the text and figures.

Author Response

Please look at the joint pdf.

Author Response File: Author Response.pdf

Reviewer 2 Report

The authors present an excellent review on the angular quasi-phase-matching elegantly combining theoretical studies with experimental work. The content of the work is clear and well-explained. The English is fluent and correct.

I have no comments on the physics of the paper but like to ask the authors to correct some minor slips in the text and organize the references according to journal’s rules.

Detailed comments:

Lines 110-111: The indices of n and lambda in these two equations do not appear to be correct (they should have the sequence 3-1-2 instead of 3-3-3).

Table 4 (page 8): The equations for the cases IV eee and V eee lack each two right brackets  in the end.

I suggest the authors to verify also the remainder of the equations ... most likely something else escaped my attention.

The font for the numbers and units should be harmonized throughout the text (e.g. in the caption of Fig. 6 the numbers in front of “µm” are different from those in front of “mm”).

 References:

Please harmonize the references (there a several styles used for journal names, volume and issue numbers, years).  Use the style of the journal.

In some references the paper titles are missing.

Reference 28: the link is not working.

 

Author Response

Please look at the joint pdf.

Author Response File: Author Response.pdf