Surface Photonic Crystal Engineering of a Multi-Mode VCSEL for a Bit-Loaded Broadband QAM-OFDM Data Link at 99 Gbit/s

Round 1

Reviewer 1 Report

Please see the review attached.

Comments for author File: Comments.pdf

Author Response

National Taiwan University

Graduate Institute of Photonics and Optoelectronics (GIPO)

Department of Electrical Engineering

1, Roosevelt Rd. Sec. 4, Taipei 10617, Taiwan R.O.C.

------------------------------------------------------------------------------------------------

Dear Editor:

 

We would like to re-submit a manuscript (Article Number: photonics-2280979) entitled “Surface Photonic Crystal Engineering of Multi-Mode VCSEL for Bit-Loaded Broadband QAM-OFDM Data Link at 99 Gbit/s” for your consideration of publication in Photonics. This manuscript has been carefully revised according to reviewer’s comments. Please allow us the last opportunity to reconsider the manuscript for publication again. We sincerely appreciate your kind help.

 

 

 

Best regards,

Gong-Ru Lin

=========================================

Professor, FIEEE, FOSA, FSPIE, FIET, FInstP

Chairman, Graduate Institute of Photonics and Optoelectronics

Department of Electrical Engineering

National Taiwan University

1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan R.O.C.

E-mail: [email protected]

Phone: +886-2-33663700 ext. 6519

Fax: +886-2-33669598

Author Response File: Author Response.pdf

Reviewer 2 Report

The article presented by the authors has some scientifically interesting aspects, but reading it is very difficult due to the lack of clarity in its exposition. In particular, the figures that are intended to clarify the aspects described in the text are difficult to read, making the text very problematic. I refer in particular to figure 3 a, b and d.

As well as in Figures 7, 8 , 9 and 10.

Since the scientific aspect is interesting, I suggest to the authors to reduce the number of figures, so as to present a text with larger and more readable figures. This might help a better understanding of the text.

 

 

 

 

Author Response

National Taiwan University

Graduate Institute of Photonics and Optoelectronics (GIPO)

Department of Electrical Engineering

1, Roosevelt Rd. Sec. 4, Taipei 10617, Taiwan R.O.C.

------------------------------------------------------------------------------------------------

Dear Editor:

 

We would like to re-submit a manuscript (Article Number: photonics-2280979) entitled “Surface Photonic Crystal Engineering of Multi-Mode VCSEL for Bit-Loaded Broadband QAM-OFDM Data Link at 99 Gbit/s” for your consideration of publication in Photonics. This manuscript has been carefully revised according to reviewer’s comments. Please allow us the last opportunity to reconsider the manuscript for publication again. We sincerely appreciate your kind help.

 

 

 

Best regards,

Gong-Ru Lin

=========================================

Professor, FIEEE, FOSA, FSPIE, FIET, FInstP

Chairman, Graduate Institute of Photonics and Optoelectronics

Department of Electrical Engineering

National Taiwan University

1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan R.O.C.

E-mail: [email protected]

Phone: +886-2-33663700 ext. 6519

Fax: +886-2-33669598

Author Response File: Author Response.pdf

Reviewer 3 Report

1) In the Abstract the terms “Coreflat+Cladflat” and “ 

 Coreflat+Cladphc2/Corephc1+Cladphc2” are confusing. What is meant by “flat”? Only after reading further and looking at Figure 1 will the reader possibly understand these terms.  

 

2) On Line 25 add “(BTB)” after the text, “… back-to-back . . .  so, the reader can understand the use of BtB on Line 30. 

3) On Line 46 use a lower case “z” in zinc. 

4) On Line 60, to be consistent, add a hyphen, thus write " . . . 71-Gbit/s . . . “. 

5) In Figure you show an n-metal contact within the n-doped bottom AlGaAs DBR. On what layer do you place the n-metal? How thick is this DBR layer (a quarter-lambda thick or larger)? Why do you have a metal contact on the substrate? 

6) On Lines 122 and 123 you write, “ . . . a lift-off process removes the un-etching SiO2 layer for coating the metal contacts . . .”. Please explain what lift off process you mean. 

7) On Line 132 you present “a” and “b” parameters (hole spacings? pitch ratios?) – please define these parameters and if useful show them in Figure 1. I understand the terms are likely defined in one of your references. 

8) Line 226 it appears “High-order” is extra text. 

9) Line 376, can you add a reference for the bit loading technique? 

Author Response

National Taiwan University

Graduate Institute of Photonics and Optoelectronics (GIPO)

Department of Electrical Engineering

1, Roosevelt Rd. Sec. 4, Taipei 10617, Taiwan R.O.C.

------------------------------------------------------------------------------------------------

Dear Editor:

 

We would like to re-submit a manuscript (Article Number: photonics-2280979) entitled “Surface Photonic Crystal Engineering of Multi-Mode VCSEL for Bit-Loaded Broadband QAM-OFDM Data Link at 99 Gbit/s” for your consideration of publication in Photonics. This manuscript has been carefully revised according to reviewer’s comments. Please allow us the last opportunity to reconsider the manuscript for publication again. We sincerely appreciate your kind help.

 

 

 

Best regards,

Gong-Ru Lin

=========================================

Professor, FIEEE, FOSA, FSPIE, FIET, FInstP

Chairman, Graduate Institute of Photonics and Optoelectronics

Department of Electrical Engineering

National Taiwan University

1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan R.O.C.

E-mail: [email protected]

Phone: +886-2-33663700 ext. 6519

Fax: +886-2-33669598

Author Response File: Author Response.pdf

Reviewer 4 Report

The manuscript presents extensive experimental comparisons between the performance of a conventional VCSEL and two "photonic-crystal-engineered" variants.

It is an interesting work, but in my opinion the authors should spend some efforts to improve its readability and to provide some missing information about the devices under study. In detail:

 - the use of tables is strongly encouraged in order to replace or complement whole pages replete with sentences such as "to decrease its subcarriers to 25/20/54/9/16 with corresponding bandwidth of 5.9/4.7/12.7/2.1/3.8 GHz with respectively receiving SNR and BER of 18.8/16.7/14/10/6.7 dB, and 2.2×10-3 /8.4×10-4 /4.5×10-4 /8.1×10-4 /1.2×10-4"

 - the notation used is cumbersome, with countless examples of sentences such as

"Next, the Core_phc1+Clad_phc2 PhC VCSEL is compared to the Core_flat+Clad_phc2 PhC VCSEL"

which could become e.g.

"Next, device (1) is compared to device (1)"

and would save one full page in the printed version and an headache to the readers
 
 - in the first device, I could not find the extension of the proton implantation, which defines the size of the cladding. From Fig.1 one could estimate it at about 1.5 periods (6 um), but an explicit statement should be in order, along with notes on the definition and accuracy of the implantation technique
 
 - in the "photonic-crystal-engineered" VCSELs, I wonder if defining the confining structure a photonic crystal (rather than e.g. a patterned mirror) is appropriate, since the period of the hole pattern is 5 times the wavelength
 
 - in the hole-patterned devices, I am not sure about the position of the contact and the width of the core

Author Response

National Taiwan University

Graduate Institute of Photonics and Optoelectronics (GIPO)

Department of Electrical Engineering

1, Roosevelt Rd. Sec. 4, Taipei 10617, Taiwan R.O.C.

------------------------------------------------------------------------------------------------

Dear Editor:

 

We would like to re-submit a manuscript (Article Number: photonics-2280979) entitled “Surface Photonic Crystal Engineering of Multi-Mode VCSEL for Bit-Loaded Broadband QAM-OFDM Data Link at 99 Gbit/s” for your consideration of publication in Photonics. This manuscript has been carefully revised according to reviewer’s comments. Please allow us the last opportunity to reconsider the manuscript for publication again. We sincerely appreciate your kind help.

 

 

 

Best regards,

Gong-Ru Lin

=========================================

Professor, FIEEE, FOSA, FSPIE, FIET, FInstP

Chairman, Graduate Institute of Photonics and Optoelectronics

Department of Electrical Engineering

National Taiwan University

1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan R.O.C.

E-mail: [email protected]

Phone: +886-2-33663700 ext. 6519

Fax: +886-2-33669598

Author Response File: Author Response.pdf

Round 2

Reviewer 4 Report

The authors answered in a satisfactory manner to all my questions. In my opinion, the revised manuscript can be published in its present form.