CHAPTER 1 Introduction 1
1.1 Historical Perspective 1
1.2 Fiber Characteristics 3
1.2.1 Material and Fabrication 4
1.2.2 Fiber Losses 5
1.2.3 Chromatic Dispersion 6
1.2.4 Polarization-Mode Dispersion 11
1.3 Fiber Nonlinearities 15
1.3.1 Nonlinear Refraction 15
1.3.2 Stimulated Inelastic Scattering 16
1.3.3 Importance of Nonlinear Effects 18
1.4 Overview 19
Problems 21
References 22
CHAPTER 2 Pulse Propagation in Fibers 27
2.1 Maxwell's Equations 27
2.2 Fiber Modes 30
2.2.1 Eigenvalue Equation 30
2.2.2 Single-Mode Condition 31
2.2.3 Characteristics of the Fundamental Mode 32
2.3 Pulse-Propagation Equation 34
2.3.1 Nonlinear Pulse Propagation 34
2.3.2 Higher-Order Nonlinear Effects 39
2.3.3 Raman Response Function and its Impact 41
2.3.4 Extension to Multimode Fibers 45
2.4 Numerical Methods 47
2.4.1 Split-Step Fourier Method 47
2.4.2 Finite-Difference Methods 51
Problems 52
References 53
CHAPTER 3 Group-Velocity Dispersion 57
3.1 Different Propagation Regimes 57
3.2 Dispersion-Induced Pulse Broadening 59
3.2.1 Gaussian Pulses 60
3.2.2 Chirped Gaussian Pulses 62
3.2.3 Hyperbolic-Secant Pulses 64
3.2.4 Super-Gaussian Pulses 65
3.2.5 Experimental Results 67
3.3 Third-Order Dispersion 68
3.3.1 Evolution of Chirped Gaussian Pulses 69
3.3.2 Broadening Factor 71
3.3.3 Arbitrary-Shape Pulses 74
3.3.4 Ultrashort-Pulse Measurements 76
3.4 Dispersion Management 78
3.4.1 GVD-Induced Limitations 78
3.4.2 Dispersion Compensation 80
3.4.3 Compensation of Third-Order Dispersion 81
Problems 83
References 84
CHAPTER 4 Self-Phase Modulation 87
4.1 SPM-Induced Spectral Changes 87
4.1.1 Nonlinear Phase Shift 88
4.1.2 Changes in Pulse Spectra 90
4.1.3 Effect of Pulse Shape and Initial Chirp 93
4.1.4 Effect of Partial Coherence 96
4.2 Effect of Group-Velocity Dispersion 98
4.2.1 Pulse Evolution 98
4.2.2 Broadening Factor 100
4.2.3 Optical Wave Breaking 102
4.2.4 Experimental Results 105
4.2.5 Effect of Third-Order Dispersion 106
4.2.6 SPM Effects in Fiber Amplifiers 108
4.3 Semianalytic Techniques 111
4.3.1 Moment Method 111
4.3.2 Variational Method 112
4.3.3 Specific Analytic Solutions 114
4.4 Higher-Order Nonlinear Effects 115
4.4.1 Self-Steepening 116
4.4.2 Effect of GVD on Optical Shocks 119
4.4.3 Intrapulse Raman Scattering 121
Problems 124
References 125
CHAPTER 5 Optical Solitons 129
5.1 Modulation Instability 129
5.1.1 Linear Stability Analysis 130
5.1.2 Gain Spectrum 131
5.1.3 Experimental Results 133
5.1.4 Ultrashort Pulse Generation 135
5.1.5 Impact on Lightwave Systems 137
5.2 Fiber Solitons 139
5.2.1 Inverse Scattering Method 140
5.2.2 Fundamental Soliton 142
5.2.3 Second and Higher-Order Solitons 144
5.2.4 Experimental Confirmation 147
5.2.5 Soliton Stability 148
5.3 Other Types of Solitons 151
5.3.1 Dark Solitons 151
5.3.2 Bistable Solitons 154
5.3.3 Dispersion-Managed Solitons 156
5.3.4 Optical Similaritons 156
5.4 Perturbation of Solitons 159
5.4.1 Perturbation Methods 159
5.4.2 Fiber Losses 161
5.4.3 Soliton Amplification 163
5.4.4 Soliton Interaction 166
5.5 Higher-Order Effects 170
5.5.1 Moment Equations for Pulse Parameters 170
5.5.2 Third-Order Dispersion 172
5.5.3 Self-Steepening 174
5.5.4 Intrapulse Raman Scattering 176
5.5.5 Propagation of Femtosecond Pulses 181
Problems 183
References 184
CHAPTER 6 Polarization Effects 193
6.1 Nonlinear Birefringence 193
6.1.1 Origin of Nonlinear Birefringence 194
6.1.2 Coupled-Mode Equations 196
6.1.3 Elliptically Birefringent Fibers 197
6.2 Nonlinear Phase Shift 199
6.2.1 Nondispersive XPM 199
6.2.2 Optical Kerr Effect 200
6.2.3 Pulse Shaping 204
6.3 Evolution of Polarization State 206
6.3.1 Analytic Solution 207
6.3.2 Poincaré-Sphere Representation 209
6.3.3 Polarization Instability 212
6.3.4 Polarization Chaos 214
6.4 Vector Modulation Instability 215
6.4.1 Low-Birefringence Fibers 215
6.4.2 High-Birefringence Fibers 218
6.4.3 Isotropic Fibers 220
6.4.4 Experimental Results 221
6.5 Birefringence and Solitons 224
6.5.1 Low-Birefringence Fibers 225
6.5.2 High-Birefringence Fibers 226
6.5.3 Soliton-Dragging Logic Gates 229
6.5.4 Vector Solitons 230
6.6 Random Birefringence 233
6.6.1 Polarization-Mode Dispersion 233
6.6.2 Vector Form of the NLS Equation 234
6.6.3 Effects of PMD on Solitons 236
Problems 239
References 240
CHAPTER 7 Cross-Phase Modulation 245
7.1 XPM-Induced Nonlinear Coupling 246
7.1.1 Nonlinear Refractive Index 246
7.1.2 Coupled NLS Equations 247
7.2 XPM-Induced Modulation Instability 248
7.2.1 Linear Stability Analysis 249
7.2.2 Experimental Results 251
7.3 XPM-Paired Solitons 252
7.3.1 Bright-Dark Soliton Pair 252
7.3.2 Bright-Gray Soliton Pair 254
7.3.3 Periodic Solutions 255
7.3.4 Multiple Coupled NLS Equations 256
7.4 Spectral and Temporal Effects 258
7.4.1 Asymmetric Spectral Broadening 259
7.4.2 Asymmetric Temporal Changes 264
7.4.3 Higher-Order Nonlinear Effects 267
7.5 Applications of XPM 268
7.5.1 XPM-Induced Pulse Compression 268
7.5.2 XPM-Induced Optical Switching 270
7.5.3 XPM-Induced Nonreciprocity 272
7.6 Polarization Effects 274
7.6.1 Vector Theory of XPM 274
7.6.2 Polarization Evolution 275
7.6.3 Polarization-Dependent Spectral Broadening 278
7.6.4 Pulse Trapping and Compression 280
7.6.5 XPM-Induced Wave Breaking 282
7.7 XPM Effects in Birefringent Fibers 284
7.7.1 Fibers with Low Birefringence 284
7.7.2 Fibers with High Birefringence 287
Problems 289
References 290
CHAPTER 8 Stimulated Raman Scattering 295
8.1 Basic Concepts 295
8.1.1 Raman-Gain Spectrum 296
8.1.2 Raman Threshold 297
8.1.3 Coupled Amplitude Equations 300
8.1.4 Effect of Four-Wave Mixing 303
8.2 Quasi-Continuous SRS 305
8.2.1 Single-Pass Raman Generation 305
8.2.2 Raman Fiber Lasers 307
8.2.3 Raman Fiber Amplifiers 310
8.2.4 Raman-Induced Crosstalk 315
8.3 SRS with Short Pump Pulses 316
8.3.1 Pulse-Propagation Equations 317
8.3.2 Nondispersive Case 318
8.3.3 Effects of GVD 320
8.3.4 Raman-Induced Index Changes 323
8.3.5 Experimental Results 325
8.3.6 Synchronously Pumped Raman Lasers 328
8.3.7 Short-Pulse Raman Amplification 330
8.4 Soliton Effects 331
8.4.1 Raman Solitons 331
8.4.2 Raman Soliton Lasers 335
8.4.3 Soliton-Effect Pulse Compression 338
8.5 Polarization Effects 339
8.5.1 Vector Theory of Raman Amplification 339
8.5.2 PMD Effects on Raman Amplification 343
Problems 346
References 347
CHAPTER 9 Stimulated Brillouin Scattering 353
9.1 Basic Concepts 353
9.1.1 Physical Process 354
9.1.2 Brillouin-Gain Spectrum 354
9.2 Quasi-CW SBS 358
9.2.1 Brillouin Threshold 358
9.2.2 Polarization Effects 359
9.2.3 Techniques for Controlling the SBS Threshold 360
9.2.4 Experimental Results 363
9.3 Brillouin-Fiber Amplifiers 366
9.3.1 Gain Saturation 366
9.3.2 Amplifier Design and Applications 367
9.4 SBS Dynamics 370
9.4.1 Coupled Amplitude Equations 370
9.4.2 SBS with Q-Switched Pulses 372
9.4.3 SBS-Induced Index Changes 376
9.4.4 Relaxation Oscillations 380
9.4.5 Modulation Instability and Chaos 382
9.5 Brillouin-Fiber Lasers 384
9.5.1 CW Operation 384
9.5.2 Pulsed Operation 388
Problems 391
References 392
CHAPTER 10 Four-Wave Mixing 397
10.1 Origin of Four-Wave Mixing 397
10.2 Theory of Four-Wave Mixing 399
10.2.1 Coupled Amplitude Equations 400
10.2.2 Approximate Solution 401
10.2.3 Effect of Phase Matching 402
10.2.4 Ultrafast Four-Wave Mixing 404
10.3 Phase-Matching Techniques 405
10.3.1 Physical Mechanisms 405
10.3.2 Phase Matching in Multimode Fibers 406
10.3.3 Phase Matching in Single-Mode Fibers 409
10.3.4 Phase Matching in Birefringent Fibers 414
10.4 Parametric Amplification 417
10.4.1 Review of Early Work 417
10.4.2 Gain Spectrum and Its Bandwidth 418
10.4.3 Single-Pump Configuration 421
10.4.4 Dual-Pump Configuration 425
10.4.5 Effects of Pump Depletion 430
10.5 Polarization Effects 431
10.5.1 Vector Theory of Four-Wave Mixing 432
10.5.2 Polarization Dependence of Parametric Gain 434
10.5.3 Linearly and Circularly Polarized Pumps 437
10.5.4 Effect of Residual Fiber Birefringence 439
10.6 Applications of Four-Wave Mixing 443
10.6.1 Parametric Oscillators 443
10.6.2 Ultrafast Signal Processing 445
10.6.3 Quantum Correlation and Noise Squeezing 447
10.6.4 Phase-Sensitive Amplification 449
Problems 451
References 452
CHAPTER 11 Highly Nonlinear Fibers 457
11.1 Nonlinear Parameter 457
11.1.1 Units and Values of n2 458
11.1.2 SPM-Based Techniques 459
11.1.3 XPM-Based Technique 462
11.1.4 FWM-Based Technique 463
11.1.5 Variations in n2 Values 464
11.2 Fibers with Silica Cladding 467
11.3 Tapered Fibers with Air Cladding 469
11.4 Microstructured Fibers 474
11.4.1 Design and Fabrication 474
11.4.2 Modal and Dispersive Properties 476
11.4.3 Hollow-Core Photonic Crystal Fibers 478
11.4.4 Bragg Fibers 480
11.5 Non-Silica Fibers 481
11.5.1 Lead-Silicate Fibers 482
11.5.2 Chalcogenide Fibers 485
11.5.3 Bismuth-Oxide Fibers 486
11.6 Pulse Propagation in Narrow-Core Fibers 487
11.6.1 Vectorial Theory 487
11.6.2 Frequency-Dependent Mode Profiles 489
Problems 491
References 492
CHAPTER 12 Novel Nonlinear Phenomena 497
12.1 Soliton Fission and Dispersive Waves 497
12.1.1 Fission of Second-and Higher-Order Solitons 498
12.1.2 Generation of Dispersive Waves 501
12.2 Intrapulse Raman Scattering 506
12.2.1 Enhanced RIFS Through Soliton Fission 506
12.2.2 Cross-correlation Technique 510
12.2.3 Wavelength Tuning through RIFS 512
12.2.4 Effects of Birefringence 514
12.2.5 Suppression of Raman-Induced Frequency Shifts 516
12.2.6 Soliton Dynamics Near a Zero-Dispersion Wavelength 520
12.2.7 Multipeak Raman Solitons 523
12.3 Four-Wave Mixing 526
12.3.1 Role of Fourth-Order Dispersion 526
12.3.2 Role of Fiber Birefringence 527
12.3.3 Parametric Amplifiers and Wavelength Converters 531
12.3.4 Tunable Fiber-Optic Parametric Oscillators 532
12.4 Second-Harmonic Generation 534
12.4.1 Physical Mechanisms 534
12.4.2 Thermal Poling and Quasi-Phase Matching 536
12.4.3 SHG Theory 539
12.5 Third-Harmonic Generation 541
12.5.1 THG in Highly Nonlinear Fibers 541
12.5.2 Effects of Group-Velocity Mismatch 543
12.5.3 Effects of Fiber Birefringence 545
Problems 546
References 547
CHAPTER 13 Supercontinuum Generation 553
13.1 Pumping with Picosecond Pulses 553
13.1.1 Nonlinear Mechanisms 554
13.1.2 Experimental Progress After 2000 556
13.2 Pumping with Femtosecond Pulses 559
13.2.1 Microstructured Silica Fibers 559
13.2.2 Microstructured Nonsilica Fibers 563
13.3 Temporal and Spectral Evolutions 566
13.3.1 Numerical Modeling of Supercontinuum 566
13.3.2 Role of Cross-Phase Modulation 570
13.3.3 XPM-Induced Trapping 573
13.3.4 Role of Four-Wave Mixing 577
13.4 CW or Quasi-CW Pumping 579
13.4.1 Nonlinear Mechanisms 579
13.4.2 Experimental Progress 582
13.5 Polarization Effects 585
13.5.1 Birefringent Microstructured Fibers 586
13.5.2 Nearly Isotropic Fibers 587
13.5.3 Nonlinear Polarization Rotation in Isotropic Fibers 589
13.6 Coherence Properties 590
13.6.1 Spectral-Domain Degree of Coherence 591
13.6.2 Techniques for Improving Coherence 594
13.6.3 Spectral Incoherent Solitons 596
13.7 Optical Rogue Waves 598
13.7.1 L-Shaped Statistics of Pulse-to-Pulse Fluctuations 599
13.7.2 Techniques for Controlling Rogue-Wave Statistics 600
13.7.3 Modulation Instability Revisited 602
Problems 606
References 607
Appendix A System of Units 613
Appendix B Numerical Code for the NLS Equation 615
Appendix C List of Acronyms 619
Index 621