UNIVERSITI PUTRA MALAYSIA

HISHAM K. HISHAM AL MUSAWI

FK 2012 61

ENHANCED DESIGN OF FIBER GRATING FABRY-PEROT LASER FOR DENSE WAVELENGTH DIVISION MULTIPLEXING SYSTEMS

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ENHANCED DESIGN OF FIBER GRATING FABRY-PEROT LASER FOR DENSE

WAVELENGTH DIVISION MULTIPLEXING SYSTEMS

HISHAM K. HISHAM AL MUSAWI

DOCTOR OF PHILOSOPHY

UNIVERSITI PUTRA MALAYSIA

2012

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ENHANCED DESIGN OF FIBER GRATING FABRY-PEROT LASER FOR DENSE WAVELENGTH DIVISION MULTIPLEXING SYSTEMS

By

HISHAM K. HISHAM AL MUSAWI

Thesis Submitted to the School of Graduate Studies, Universiti Putra Malaysia, in Fulfillment of the Requirement for the Degree of Doctor of Philosophy

July 2012

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DEDICATION

To my parents,

To my Beloved wife and my children

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Abstract of the thesis presented to the Senate of Universiti Putra Malaysia in fulfillment of the requirement for the degree of Doctor of Philosophy

ENHANCED DESIGN OF FIBER GRATING FABRY-PEROT LASER FOR

DENSE WAVELENGTH DIVISION MULTIPLEXING SYSTEMS

By

HISHAM K. HISHAM AL MUSAWI

July 2012

Chairman: Assoc. Prof. Ahmad Fauzi Abas, PhD Faculty: Engineering

Semiconductor laser diodes (SLDs) have been widely used in wavelength-division-

multiplexing (WDM) systems due to small size, low power consumption, fast response,

and its ability to perform direct modulation at moderate bit rates. A major obstacle

preventing closer channel spacing is the drift of emission wavelength with ambient

temperature variation. Therefore, with the development of dense WDM (DWDM)

systems, lasers with narrow linewidth, high side mode suppressed ratio (SMSR), low

chirp, low cost, and stable dynamic single-mode operation are indispensable.

In recent years, fiber grating Fabry-Perot (FGFP) laser is proposed as an alternative light

source for WDM systems, which can generate light with highly stable wavelengths. This

is because; the emission wavelength of such laser depends only on the Bragg wavelength

of fiber grating (FG), thus, independent of chip temperature and injection current.

However, FGFP laser output experiences phase fluctuations due to the quantum nature

of the light. In addition, ambient temperature variation causes fluctuation in the gain

spectrum, threshold current, and other cavity parameters. Furthermore, external optical

feedback (OFB) level (i.e. the light reflected back from grating fiber) significantly

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affects the performance of FGFP laser, which may fluctuate the FGFP light intensity and

varies the dynamical and spectral behaviors of the laser. These will produce unwanted

effect such as mode hopping and/or the coherence collapse.

In this thesis, the performance of the FGFP laser is enhanced by optimizing parameters

in its original model. The effect of ambient temperature variation, OFB, injection

current, cavity volume, nonlinear gain compression factor, spontaneous emission factor,

linewidth enhancement factor, antireflection (AR) coating reflectivity, external cavity

length, amplitude coupling coefficient, and fiber Bragg grating (FBG) parameters on the

performance characteristics of the FGFP laser, namely dynamic response (transient

response, turn-on time delay, relaxation oscillation frequency), modulation responses

(intensity modulation, frequency modulation) and noise characteristics (relative intensity

noise, phase noise, linewidth characteristics) has been demonstrated. In this study, we

modeled FGFP laser based on the three-mirror laser cavity model. The reflection from

the external mirror is combined with the reflection of the laser end front facet, ending up

with a complex-valued effective reflection coefficient, which is equivalent to two-mirror

cavity. The expressions that describe the laser characteristics have been modified by

considering the effect of temperature, external OFB and other external cavity

parameters.

This thesis is presented based on the alternative format which has been approved by

University Putra Malaysia’s Senate, which is the manuscript-based format. The major

difference between this alternative format and the conventional ones is that, this format

uses published papers in place of the regular chapters on the results and discussion.

The first paper, which deals with the turn-on time delay characteristics of the

semiconductor diode lasers, is a comment paper, contains new results of the effect of the

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carrier recombination rate coefficients on the laser turn-on time delay which is published

in Optics and Laser Technology. This journal in indexed by ISI Thomson Scientific with

2010 impact factor of 1.616. The results in this paper corrected the misconception to the

behavior of the carrier recombination rate coefficients on the laser turn-on time

delay, which has been published by Zhang et al, Opt. & Laser Technol. 39 (2007) 997–

1001. This paper is based on a numerical closed-form equation for turn-on time delay in

terms of all carrier recombination rate coefficients. The comparison between our results

and those that has been published was based on the practical and physical concepts for

the operation principle of semiconductor lasers. It has been shown that the main effect

of increasing any of the carrier recombination rate coefficients is to increase the turn-on

time delay (not to decrease, as in original report), which is due to increase of the carrier-

recombination rate. This fact has been supported further by investigating the effect of

carrier recombination rate coefficients on the laser threshold current.

The second paper contains a comprehensive analysis on FGFP laser peak intensity

modulation and relaxation oscillation frequency (ROF) characteristics, which is

published in Optical Review, the Japan Society of Applied Physics. This journal in

indexed by ISI Thomson Scientific with 2010 impact factor of 0.55. The frequency of

the relaxation oscillation plays an important role in determining laser response. The

study is performed by modifying the general expression of ROF equation, which is often

expressed in terms of the carrier and photon lifetimes. It is demonstrated that by

optimizing design parameters, ROF increased significantly to produce high flat

frequency operation.

The third paper investigated the FGFP laser modulation response characteristics, which

is published in Optics and Laser Technology. This journal in indexed by ISI Thomson

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Scientific with 2010 impact factor of 1.616. In this paper, a unified and comprehensive

study on the small-signal intensity modulation (IM) and frequency modulation (FM)

characteristics of FGFP laser have been numerically conducted. This study has been

presented by developing the general expressions of the intensity and frequency

modulations response using the single-mode laser rate equation. It was shown that with

laser dimension optimization, IM and FM responses with low peak amplitude, high flat

frequency operation and high temperature stability can be obtained.

The most important feature of a semiconductor laser used in optical communication

systems is the ability to operate with low relative intensity noise. In the fourth paper, we

present a comprehensive analysis on the FGFP laser relative intensity noise (RIN)

characteristics, which is published in IEEE Journal Quantum Electronics. This journal is

indexed by ISI Thomson Scientific with 2010 impact factor of 2.48. In this paper, the

analysis has been performed numerically by developing a set of nonlinear single-mode

laser rate equations. It is shown that by laser optimization, the relative intensity noise

level of FGFP laser can be reduced significantly.

Finally, the phase noise characteristics of a semiconductor laser are of interest in

evaluating the performance of a coherent optical communication system. Because of the

quantum nature of the lasing process, the laser output exhibits phase as well as intensity

fluctuations. The fifth paper discussed the phase noise characteristics of FGFP laser,

which is published in the Journal of Modern Optics. This journal in indexed by ISI

Thomson Scientific with 2010 impact factor of 0.988. In this paper, the analysis was

performed numerically by modifying the general expression of the laser phase noise

equation. Through a comprehensive analysis, the results clearly show that by laser

optimization, the FGFP laser phase noise performances significantly improved.

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Abstrak tesis dikemukakan kepada Senat Universiti Putra Malaysia sebagai memenuhi keperluan untuk ijazah Doktor Falsafah

DIPERTINGKATKAN REKABENTUK BAGI GENTIAN PARUTAN FABRY-

PEROT LASER UNTUK SISTEM PEMULTIPLEKSAN PEMBAHAGIAN PANJANG GELOMBANG PADAT

Oleh

HISHAM K. HISHAM AL MUSAWI

Julai 2012

Pengerusi: Prof. Madya Ahmad Fauzi Abas, PhD Fakulti: Kejuruteraan

Semikonduktor diod laser (SLDs) telah digunakan secara meluas dalam sistem

pemultipleksan pembahagian-panjang-gelombang (WDM) kerana saiz yang kecil,

penggunaan tenaga yang rendah, tindak balas yang cepat, dan keupayaan untuk

melaksanakan modulasi langsung pada kadar bit yang sederhana. Satu kekangan utama

yang menghadkan saiz saluran yang lebih kecil adalah hanyutan pancaran panjang

gelombang yang berkadar dengan perubahan suhu persekitaran. Oleh itu, dengan

pembangunan sistem WDM padat (DWDM), laser dengan lebar-garis yang sempit,

nisbah pempadatan mod sisi yang tinggi (SMSR), decit dan kos yang rendah serta

operasi dinamik mod-tunggal yang stabil adalah diperlukan.

Dalam tahun-tahun kebelakangan ini, laser gentian parutan Fabry-Perot (FGFP)

dicadangkan sebagai sumber cahaya alternatif untuk sistem WDM, yang mana ia boleh

menjana cahaya dengan panjang gelombang yang amat stabil. Ini adalah kerana panjang

gelombang pancaran laser tersebut hanya bergantung pada panjang gelombang gentian

parutan Bragg (FG), oleh itu ia bebas daripada suhu cip dan arus suntikan. Walau

bagaimanapun, keluaran laser FGFP mengalami turun naik fasa kerana sifat kuantum

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cahaya. Tambahan pula, perubahan suhu persekitaran menyebabkan ketidakstabilan

gandaan spektrum, kadar arus dan parameter rongga yang lain. Seterusnya, tahap suapan

semula optik luaran (OFB), iaitu cahaya dipantulkan kembali dari gentian parutan sangat

mempengaruhi prestasi laser FGFP yang boleh mengubah turun naik cahaya FGFP dan

mempelbagai tingkah laku dinamik dan spektrum laser. Ini akan menghasilkan kesan

yang tidak diingini seperti melompat mod dan/atau keruntuhan koheren.

Dalam tesis ini, prestasi laser FGFP dipertingkatkan dengan mengoptimumkan

parameter dalam model asalnya. Kesan-kesan berikut telah ditunjukkan; perubahan suhu

persekitaran, OFB, suntikan arus, isipadu rongga, faktor mampatan gandaan tidak linear,

faktor pelepasan spontan, faktor peningkatan lebar-garis, tindak balas salutan

antipantulan (AR), panjang rongga luaran, pekali gandingan amplitud dan parameter

gentian parutan Bragg (FBG) pada ciri-ciri prestasi laser FGFP, iaitu tindak balas

dinamik (tindak balas transient, tangguhan masa hidup, kekerapan kelonggaran ayunan),

tindak balas modulasi (modulasi keamatan modulasi frekuensi) dan ciri-ciri kebisingan

(kekuatan kebisingan relatif, fasa kebisingan, ciri-ciri lebar-garis). Dalam kajian ini,

kami memodelkan laser FGFP berdasarkan model laser rongga tiga cermin. Pantulan

dari cermin luaran digabungkan dengan pantulan hujung facet laser, yang berkesudahan

dengan nilai kompleks pekali pantulan berkesan, yang bersamaan dengan rongga dua

cermin. Rumus yang menghuraikan ciri-ciri model laser telah diubahsuai dengan

mengambil kira kesan suhu, OFB luaran dan lain-lain parameter rongga luar untuk

analisa prestasi model secara komprehensif.

Tesis ini disampaikan berdasarkan format alternatif yang telah diluluskan oleh Senat

Universiti Putra Malaysia, iaitu berasaskan format manuskrip. Perbezaan utama antara

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format alternatif ini dari yang konvensional ia mengemukakan kompilasi kertas kerja

yang telah diterbitkan, mengantikan bab-bab keputusan dan perbincangan.

Kertas kerja pertama adalah berkaitan dengan ciri-ciri tangguhan masa penghidupan

pada laser diod semikonduktor, merupakan kertas kerja ulasan yang mengandungi

keputusan baru dalam kesan pekali kadar penggabungan pembawa semula pada

tqangguhan masa penghidupan laser yang disiarkan dalam Laser dan Optik Teknologi.

Jurnal ini diindeks oleh ISI Thomson Saintifik dengan Impact Factor pada 2010

sebanyak 1.616. Keputusan dalam kertas ini membetulkan salah tanggapan kepada

kelakuan pekali kadar penggabungan pembawa semula pada laser seterusnya pada hela

masa yang telah diterbitkan oleh Zhang et al, Opt. & Laser Technol. 39 (2007) 997-

1001. Kertas kerja ini adalah berdasarkan persamaan bentuk tertutup berangka untuk

tangguhan masa penghidupan untuk semua pekali kadar penggabungan semula

pembawa. Perbandingan keputusan adalah berdasarkan konsep praktikal dan fizikal bagi

prinsip operasi laser semikonduktor. Ia menunjukkan kesan utama peningkatan mana-

mana pekali kadar penggabungan semula pembawa adalah dengan meningkatkan

kelewatan pusingan pada masa yang ditetapkan (tidak mengurangkan, seperti dalam

laporan asal), yang adalah disebabkan untuk meningkatkan kadar pembawa rekombinasi.

Fakta ini telah disokong lagi dengan menyiasat kesan pekali kadar penggabungan

semula pembawa di kadar arus laser.

Kertas kerja kedua mengandungi analisis komprehensif mengenai ciri-ciri modulasi

keamatan puncak dan kelonggaran frekuensi ayunan bagi laser FGFP. Kertas kerja ini

diterbitkan dalam Kajian Optik, Persatuan Fizik Gunaan Jepun yang diindeks oleh ISI

Thomson Saintifik dengan Impact Factor 2010 adalah 0.55. Kekerapan ayunan longgar

memainkan peranan yang penting dalam menentukan tindak balas laser. Kajian ini

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dilakukan dengan mengubahsuai persamaan umum ROF yang diungkapkan dari segi

pembawa dan jangka hayat foton. Ia menunjukkan bahawa dengan mengoptimumkan

reka bentuk parameter, ROF meningkat dengan ketara untuk menghasilkan operasi

frekuensi tinggi yang rata.

Kertas ketiga menyiasat tindak balas ciri-ciri pemodulatan laser FGFP yang diterbitkan

dalam Laser dan Optik Teknologi. Jurnal ini diindeks oleh ISI Thomson Saintifik

dengan Impact Factor 2010 sebanyak 1.616. Dalam kertas kerja ini, satu kajian yang

seragam dan menyeluruh telah dijalankan secara berangka ke atas ciri-ciri isyarat kecil

modulasi keamatan (IM) dan modulasi frekuensi (FM) laser FGFP. Kajian ini telah

dibentangkan dengan membangunkan ungkapan umum tindak balas modulasi keamatan

dan frekuensi menggunakan persamaan kadar laser satu mod. Ia menunjukkan bahawa

dengan mengoptimumkan dimensi laser, IM dan tindak balas FM dengan amplitud

puncak yang rendah, operasi kekerapan rata yang tinggi dan kestabilan pada suhu yang

tinggi boleh diperolehi.

Ciri paling penting bagi laser semikonduktor yang digunakan dalam sistem komunikasi

optik adalah kemampuannya beroperasi dengan keamatan gangguan relatif yang rendah.

Dalam kertas kerja keempat, kami kemukakan suatu analisis komprehensif mengenai

ciri-ciri relatif keamatan gangguan (RIN) laser FGFP, yang diterbitkan di Jurnal

Kuantum Elektronik IEEE. Jurnal ini diindeks oleh ISI Thomson Saintifik dengan

Impact Factor 2010 sebanyak 2.48. Dalam kertas ini, analisis secara numerical telah

dilakukan dengan membangunkan satu set persamaan laser mod tunggal tak berkadar

terus. Ia menunjukkan bahawa dengan mengoptimumkan laser, tahap keamatan

gangguan relatif daripada FGFP laser boleh dikurangkan dengan ketara.

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Akhirnya, ciri-ciri gangguan fasa laser semikonduktor adalah penting dalam menilai

prestasi sistem komunikasi optik yang koheren. Oleh kerana sifat kuantum proses laser,

keluaran laser menunjukkan fasa dan keamatan yang turun naik. Kertas kelima

membincangkan ciri-ciri fasa gangguan laser FGFP yang diterbitkan dalam Jurnal Optik

Moden. Jurnal ini diindeks oleh ISI Thomson Saintifik dengan Impact Factor 2010

sebanyak 0.988. Dalam kertas ini, analisis berangka telah dilakukan dengan

mengubahsuai ungkapan umum persamaan fasa gangguan laser. Melalui analisis yang

komprehensif, keputusan dengan jelas menunjukkan bahawa melalui pengoptimuman

laser, kadar fasa gangguan laser FGFP telah melalui penambahbaikan yang ketara.

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ACKNOWLEDGEMENTS

First and foremost, I wish to acknowledge the Creator of the entire world, who all the

knowledge is with Him. The infinite thanks to Him that from His mercy and kindness

forgave me the knowledge.

I would like to express my appreciation and sincere gratitude to my supervisor, Assoc.

Prof. Dr.-Ing. Ahmad Fauzi Abas, for his continued support, encouragement and endless

patience towards completing the research. These special thanks are also dedicated to

supervisory committee member; Prof. Dr. Mohd Adzir B. Mahdi and Dr. Ahmad Shukri

bin Mohammd Noor, for their invaluable guidance and constructive criticisms

throughout the success of this project.

I would also like to express my gratitude to former member of Centre of Excellence for

Wireless and Photonic Networks, Dr. Ghafour Amouzad Mahdiraji. I have acquired a

great deal of skills Ghafour, who was always willing to lend a hand specially in field of

optical communications, and am grateful to have him as a close, personal friend.

I certainly appreciate the extremely friendly environment that I had to work in. My

colleagues in Photonics and Fiber Optics Systems Laboratory, UPM, were always

willing to lend a hand or a sympathetic ear for fruitful discussions, and chats, which

have contributed towards the completion of this thesis. Working with all of you is a

good experience that could never be forgotten.

Finally, last but not least, I thank my father, my mother and my wife for their

unconditional love, support and constant encouragement. It is with them that I share this

great accomplishment.

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I certify that a Thesis Examination Committee has met on …………… to conduct the final examination of Hisham K. Hisham AL Musawi on his thesis entitled "Optimum Design of Fiber Grating Fabry-Perot Laser for Dense Wavelength Division Multiplexing Systems" in accordance with the Universities and University Colleges Act 1971 and the Constitution of the Universiti Putra Malaysia [P.U.(A) 106] 15 March 1998. The Committee recommends that the student be awarded the Doctor of Philosophy. Members of the Thesis Examination Committee were as follows: ……………………………..., PhD Professor Faculty of Engineering Universiti Putra Malaysia (Chairman) ………………………………., PhD Professor Faculty of Engineering Universiti Putra Malaysia (Internal Examiner) ……………………………….., PhD Associate Professor Faculty of Engineering Universiti Putra Malaysia (Internal Examiner) …………………………………, PhD Professor Faculty of Engineering University of Malaya (External Examiner) .

BUJANG BIN KIM HUAT, PhD Professor and Deputy Dean School of Graduate Studies Universiti Putra Malaysia

Date: …………………………….

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This thesis was submitted to the Senate of Universiti Putra Malaysia and has been accepted as fulfillment of the requirement for the degree of Doctor of Philosophy. The members of the Supervisory Committee were as follows: Ahmad Fauzi Abas, PhD, Ing Associate Professor Faculty of Engineering Universiti Putra Malaysia (Chairman) Mohd Adzir B. Mohdi, PhD Professor Faculty of Engineering Universiti Putra Malaysia (Member) Ahmed Shukri bin Mohammd Noor, PhD Senior Lecturer Faculty of Engineering Universiti Kebangsaan Malaysia (Member) .

BUJANG BIN KIM HUAT, PhD Professor and Dean School of Graduate Studies Universiti Putra Malaysia

Date:

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DECLARATION

I declare that the thesis is my original work except for quotations and citations which

have been duly acknowledged. I also declare that it has not been previously, and is not

concurrently, submitted for any other degree at Universiti Putra Malaysia or at any other

institution.

HISHAM K. HISHAM AL MUSAWI

Date:

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TABLE OF CONTENTS

Page DEDICATIONS ii ABSTRACT iii ABSTRAK vii ACKNOWLEDGEMENTS xii APPROVAL xiii DECLARATION xv LIST OF ABBREVIATIONS xx CHAPTER

1 INTRODUCTION 1.1 1.1. Background 1.1 1.2. Tunable Laser Diodes 1.3

1.2.1. Tunable Monolithic Semiconductor Lasers 1.3 1.2.1.1. Distributed Feedback Lasers 1.4 1.2.1.2. Distributed Bragg Reflector 1.4 1.2.1.3. Vertical Cavity Surface Emitting Lasers 1.5

1.2.2. Tunable External Cavity Diodes Lasers 1.6 1.3. Problem Statements 1.7 1.4. Research Objectives 1.11 1.5. Scope of Work 1.12 1.6. Thesis Organization 1.14 References 1.18

2 LITERATURE REVIEW 2.1 2.1. Evolution of Optical Fiber Communications 2.1 2.2. Semiconductor Laser Diodes 2.3

2.2.1. Semiconductor Laser Principle 2.4 2.2.1.1. External Pumping 2.4 2.2.1.2. Light Amplification 2.4

2.2.2. Fabry-Perot Laser Diode 2.5 2.2.3. Single Mode Laser Diodes 2.6

2.2.3.1. Distributed Feedback Lasers 2.6 2.2.3.2. Distributed Bragg Reflector Lasers 2.8 2.2.3.3. Cleaved-Coupled Cavity Lasers 2.9 2.2.3.4. Vertical-Cavity Surface Emitting Lasers 2.11

2.3. External Cavity Tunable Diode Lasers 2.12 2.4. Fiber Bragg Gratings 2.15

2.4.1. Fundamentals of Fiber Bragg Gratings 2.17 2.4.1.1. Coupled-Mode Theory for Bragg Gratings 2.17 2.4.1.2. Modeling of Fiber Bragg Gratings 2.20

2.4.2.Tuning Mechanisms of Fiber Grating Lasers 2.21 2.4.2.1. Strain Tuning 2.23 2.4.2.2. Temperature Tuning 2.25

2.5 Summary 2.27 References 2.28

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3 METHODOLOGY 3.1 3.1 Introduction 3.1 3.2 Research Flow 3.1 3.3 Basic Properties of fiber Bragg grating 3.3

3.3.1 Bragg Condition 3.4 3.3.2. Uniform Bragg Grating Reflectivity 3.5 3.3.3. Bragg Grating Bandwidth 3.7 3.3.4. Delay and Dispersion Characteristics 3.9

3.4 Design and Performance Parameters 3.10 3.4.1. Design Parameters 3.11

3.4.1.1. Temperature Variation 3.11 3.4.1.2. External Optical Feedback 3.12 3.4.1.3. Nonlinear Gain Compression Factor 3.12 3.4.1.4. Cavity Volume 3.13 3.4.1.5. Spontaneous Emission Factor 3.13 3.4.1.6. Antireflection Coating Reflectivity 3.14 3.4.1.7. Laser to Fiber Coupling Coefficient 3.14 3.4.1.8. External Cavity Length 3.14

3.4.2. Performance Parameters 3.15 3.4.2.1. Dynamic Response 3.15 3.4.2.2. Modulation Response 3.16 3.4.2.3. Noise Characteristics 3.17

3.5. Model Design 3.17 3.5.1. Three Mirror Laser Cavity Model 3.20 3.5.2. External Cavity Modes 3.21 3.5.3. Temperature Dependence of FGFP Laser 3.25

3.6. Methodology Flow Chart 3.25 3.6.1.Investigation on the Effect of Carrier Recombination Rate

Coefficients on Semiconductor Laser Diodes Turn-on Time Delay Characteristics 3.28

3.6.2. Improving the Performance Characteristics of FGFP Laser 3.30 3.7. Summary 3.32 References 3.33

4 COMMENT ON: “THEORETICAL CALCULATION TURN-ON TIME DELAY OF VCSEL AND EFFECT OF CARRIER RECOMBINATIONS” [Opt. & Laser Tech. 39 (2007) 997–1001] 4.1 (Optical and Laser Technology) 4.1 Acceptance Letter 4.14

5 CHARACTERIZATION OF SMALL-SIGNAL INTENSITY

MODULATION FOR SINGLE-MODE FIBER GRATING FABRY-PEROT LASER SOURCE 5.1 (Optical Review) 5.1 Acceptance Letter 5.25

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6 IMPROVING THE CHARACTERISTICS OF THE MODULATION RESPONSE FOR FIBER BRAGG GRATING FABRY-PEROT LASERS BY OPTIMIZING MODEL PARAMETERS 6.1 (Optical and Laser Technology) 6.1 Acceptance Letter 6.30

7 RELATIVE INTENSITY NOISE REDUCTION BY OPTIMIZING FIBER GRATING FABRY-PEROT LASER PARAMETERS 7.1

(IEEE Journal Quantum Electronics) 7.1 Acceptance Letter 7.29

8 CHARACTERIZATION OF PHASE NOISE IN SINGLE-MODE FIBER

GRATING FABRY-PEROT LASER 8.1 (Journal of Modern Optics) 8.1

Acceptance Letter 8.30

9 DISCUSSION AND BENCHMARKING 9.1 9.1. Benchmarking of the Study 9.1 9.1.1. Turn-On Time Delay 9.1 9.1.2. Power Characteristics 9.2 9.1.3. Modulation Response 9.2 9.1.4. Noise Characteristics 9.2 9.2. The Contributions 9.3 References 9.8

10 CONCLUSION AND FUTURE WORK 10.1

Conclusion 10.1 Future Work 10.5

APPENDIX A A.1 APPENDIX B B.1 APPENDIX C C.1 APPENDIX D D.1 APPENDIX E E.1 APPENDIX F F.1 APPENDIX G G.1 BIODATA OF STUDENT H.1 LIST OF PUBLICATIONS I.1