Distributed Feedback Laser Diodes and Optical Tunable Filters

✍ Scribed by Dr. H. Ghafouri-Shiraz

• Publisher: Wiley
• Year: 2003
• Tongue: English
• Leaves: 344
• Edition: 2nd
• Category: Library

✦ Synopsis

Advances in optical fibre based communications systems have played a crucial role in the development of the information highway. By offering a single mode oscillation and narrow spectral output, distributed feedback (DFB) semiconductor laser diodes offer excellent optical light sources as well as optical filters for fibre based communications and dense wavelength division multiplexing (DWDM) systems. This comprehensive text focuses on the basic working principles of DFB laser diodes and optical filters and details the development of a new technique for enhanced system performance.Considers the optical waveguiding characteristics and properties of semiconductor materials and the physics of DFB semiconductor lasers.Presents a powerful modelling technique based on the transfer matrix method which can be used to improve the design of laser diodes, optical fibres and amplifiers.Examines the effect of the various corrugation shapes on the coupling coefficients and lasing characteristics of DFB laser diodes.Technical advice to improve immunity against the spatial hole burning effect.Extensive referencing throughout and a comprehensive glossary of symbols and abbreviations.Suitable for both introductory and advanced levelsThis is an indispensable textbook for undergraduate and postgraduate students of electrical and electronic engineering and physics as it consolidates their knowledge in this rapidly growing field. As a technical guide for the structural design of DFB laser diodes and optical filters, the book will serve as an invaluable reference for researchers in opto-electronics, and semi conductor device physics.

✦ Table of Contents

Cover......Page 1
Contents......Page 10
Preface......Page 16
Acknowledgements......Page 18
Glossary of Abbreviations......Page 20
Glossary of Symbols......Page 22
1.2 Historical Progress......Page 28
1.3 Optical Fibre Communication Systems......Page 31
1.3.2 Coherent Detection Schemes......Page 32
1.4.1 Spectral Purity Requirements......Page 34
1.4.2 Spectral Linewidth Requirements......Page 45
1.5 Summary......Page 52
1.6 References......Page 53
2.1 Introduction......Page 58
2.2.1 Absorption and Emission of Radiation......Page 59
2.2.2 The Einstein Relations and the Concept of Population Inversion......Page 60
2.2.3 Dispersive Properties of Atomic Transitions......Page 63
2.3.1 Population Inversion in Semiconductor Junctions......Page 65
2.3.2 Principle of the Fabry–Perot Etalon......Page 68
2.3.3 Structural Improvements in Semiconductor Lasers......Page 70
2.3.4 Material Gain in Semiconductor Lasers......Page 72
2.3.5 Total Radiative Recombination Rate in Semiconductors......Page 75
2.4 Coupled Wave Equations in Distributed Feedback Semiconductor Laser Diodes......Page 78
2.4.1 A Purely Index-coupled DFB Laser Diode......Page 83
2.4.2 A Mixed-coupled DFB Laser Diode......Page 84
2.4.3 A Gain-coupled or Loss-coupled DFB Laser Diode......Page 85
2.5.1 A Structural Definition of the Coupling Coefficient for DFB Semiconductor Lasers......Page 87
2.5.2 The Effect of Corrugation Shape on Coupling Coefficient......Page 89
2.5.3 Transverse Field Distribution in an Unperturbed Waveguide......Page 92
2.5.4 Results Based upon the Trapezoidal Corrugation......Page 95
2.7 References......Page 103
3.2 Solutions of the Coupled Wave Equations......Page 106
3.3 Solutions of Complex Transcendental Equations using the Newton–Raphson Approximation......Page 109
3.4 Concepts of Mode Discrimination and Gain Margin......Page 111
3.5 Threshold Analysis of a Conventional DFB Laser......Page 112
3.6 Impact of Corrugation Phase at Laser Facets......Page 114
3.7 The Effects of Phase Discontinuity along the DFB Laser Cavity......Page 116
3.7.1 Effects of Phase Shift on the Lasing Characteristics of a 1PS DFB Laser Diode......Page 119
3.7.2 Effects of Phase Shift Position (PSP) on the Lasing Characteristics of a 1PS DFB Laser Diode......Page 121
3.8 Advantages and Disadvantages of QWS DFB Laser Diodes......Page 122
3.9 Summary......Page 124
3.10 References......Page 125
4.1 Introduction......Page 128
4.2 Brief Review of Matrix Methods......Page 129
4.2.1 Formulation of Transfer Matrices......Page 130
4.2.2 Introduction of Phase Shift (or Phase Discontinuity)......Page 133
4.2.3 Effects of Finite Facet Reflectivities......Page 136
4.4 Formulation of the Amplified Spontaneous Emission Spectrum using the TMM......Page 138
4.4.1 Green's Function Method Based on the Transfer Matrix Formulation......Page 139
4.4.2 Determination of Below-Threshold Spontaneous Emission Power......Page 142
4.4.3 Numerical Results from Various DFB Laser Diodes......Page 144
4.5 Summary......Page 147
4.6 References......Page 148
5.1 Introduction......Page 150
5.2 Threshold Analysis of the Three-phase-shift (3PS) DFB Laser......Page 151
5.2.1 Effects of Phase Shift on the Lasing Characteristics......Page 152
5.2.2 Effects of Phase Shift Position (PSP) on the Lasing Characteristics......Page 153
5.3.1 Structural Impacts on the Gain Margin......Page 155
5.3.2 Structural Impacts on the Uniformity of the Internal Field Distribution......Page 157
5.4 Threshold Analysis of the Distributed Coupling Coefficient (DCC) DFB LD......Page 163
5.4.1 Effects of the Coupling Ratio on the Threshold Characteristics......Page 164
5.4.3 Optimisation of the DCC DFB Laser Structure......Page 165
5.5 Threshold Analysis of the DCC t 3PS DFB Laser Structure......Page 168
5.6 Summary......Page 172
5.7 References......Page 173
6.2 Determination of the Above-Threshold Lasing Mode using the TMM......Page 176
6.3 Features of Numerical Processing......Page 180
6.4 Numerical Results......Page 184
6.4.1 Quarterly-Wavelength-Shifted (QWS) DFB LDs......Page 185
6.4.2 Three-phase-shift (3PS) DFB LDs......Page 188
6.4.3 Distributed Coupling Coefficient with Quarterly-Wavelength-Shifted (DCC t QWS) DFB LDs......Page 191
6.4.4 Distributed Coupling Coefficient with Three-Phase-Shift (DCC t 3PS) DFB LDs......Page 192
6.5 Summary......Page 195
6.6 References......Page 196
7.1 Introduction......Page 198
7.2 Single-Mode Stability in DFB LDs......Page 199
7.3 Numerical Results on the Gain Margin of DFB LDs......Page 201
7.4 Above-Threshold Spontaneous Emission Spectrum......Page 209
7.5 Spectral Linewidth......Page 212
7.5.1 Numerical Results on Spectral Linewidth......Page 216
7.6 Summary......Page 218
7.7 References......Page 219
8.1 Introduction......Page 222
8.2 The Transmission-Line Matrix (TLM) Method......Page 223
8.2.1 TLM Link Lines......Page 224
8.2.2 TLM Stub Lines......Page 225
8.3 Scattering and Connecting Matrices......Page 226
8.4 Transmission-Line Laser Modelling (TLLM)......Page 233
8.5 Basic Construction of the Model......Page 234
8.6 Carrier Density Model......Page 235
8.7 Laser Amplification......Page 237
8.8 Carrier-induced Frequency Chirp......Page 243
8.9 Spontaneous Emission Model......Page 246
8.10 Computational Efficiency Baseband Transformation......Page 248
8.11 Signal Analysis – Post-processing Methods......Page 250
8.13 References......Page 253
9.2 DFB Laser Diodes......Page 258
9.4 A DFB Laser Diode Model with Phase Shift......Page 261
9.5.1 Scattering Matrix for a Uniform DFB LD......Page 263
9.5.2 Scattering Matrix for the DFB Laser Diode with Phase Shift......Page 265
9.6.1 Connection Matrix C for the Stubs Within a Section......Page 266
9.7 Carrier Density Rate Equation......Page 267
9.8 Results and Discussions......Page 268
9.8.1 Dynamic Characteristics......Page 269
9.8.2 Longitudinal Distribution......Page 271
9.8.3 Effects of the Number of Phase Shifts......Page 274
9.8.4 Effects of Phase Position and Value on the 3PS DFB LD's Characteristics......Page 276
9.10 References......Page 277
10.1 Introduction......Page 280
10.2 Wavelength Selection......Page 281
10.3 Solutions of the Coupled Wave Equations......Page 282
10.3.2 Formulation of the Transfer Matrix......Page 284
10.3.3 Solutions of Complex Transcendental Equations using the Newton–Raphson Approximation......Page 287
10.4 Threshold Analysis of DFB Laser Diodes......Page 289
10.4.1 Phase Discontinuities in DFB LDs......Page 290
10.4.2 Below-threshold Characteristics......Page 293
10.5 Active Tunability DFB LD Amplifier Filters......Page 295
10.6 Structural Impacts on DFB LD Amplifier Filters......Page 298
10.6.1 Phase-shift-controlled DFB LD Amplifier Filters......Page 299
10.7 New Multi-section and Phase-shift-controlled DFB LD Optical Filter Structures......Page 301
10.8 DFB LDs Versus DBR LDs......Page 306
10.9 Summary......Page 308
10.10 References......Page 309
11.1 Introduction......Page 312
11.2 Analysis......Page 313
11.3.1 A Quarter Wavelength Phase-shifted Double Phase-shift-controlled DFB LD-based Wavelength Tunable Filter......Page 316
11.3.2 A Single-phase-shift-controlled Double-phase-shift DFB Wavelength Tunable Optical Filter......Page 321
11.3.3 A Multiple-phase-shift Controlled DFB LD-based Wavelength Tunable Optical Filter......Page 325
11.4 Summary......Page 328
11.5 References......Page 329
12.1 Summary and Conclusion......Page 330
12.3.3 Further Investigation of Optical Devices to be Used in WDM......Page 334
12.4 References......Page 335
Index......Page 338