Nanostructure Semiconductor Optical Amplifiers (eBook)

Preface 5
Contents 7
1 Quantum-Dot Semiconductor Optical Amplifiers, Basic Principles, Design Methods, and Optical Characterizations 10
1.1…Introduction 10
1.2…Operation Principles 11
1.3…SOA Gain 12
1.3.1 Gain Saturation 15
1.3.2 Confinement Factor 17
1.4…Refractive Index 18
1.5…Linewidth Enhancement Factor 19
1.6…Comparison of Operating Characteristics 21
1.6.1 Amplified Spontaneous Emission 25
1.6.2 Noise Figure 26
1.7…Polarization Properties 28
1.8…Doped QD-SOAs 36
1.8.1 p-Doped QD-SOAs 37
1.8.2 n-Doped QD-SOAs 46
1.9…Fabrication Process 47
1.9.1 Quantum-Dot Growth 47
1.9.2 Epitaxial Structure of QD-SOA 49
1.9.3 Waveguide Requirements of QD-SOA 52
1.9.3.1 Far-Field Pattern 52
1.9.3.2 Facet Reflectivity Reduction 53
1.9.3.3 Anti-Reflection Coating 54
1.9.3.4 Buried Facet (Window Structure) 56
1.9.3.5 Tilted Waveguide/Facet 58
References 59
2 Simulation Methods of Quantum-Dot Semiconductor Optical Amplifiers 62
2.1…Introduction 62
2.2…Numerical Methods 63
2.3…Equivalent Circuit Methods 67
2.4…Analytical Methods 74
References 78
3 Techniques Toward High Speed Operation of Semiconductor Optical Amplifiers 80
3.1…Introduction 80
3.2…Gain Recovery Improvement Techniques in Bulk and QW-SOAs 80
3.2.1 Carrier Reservoir 80
3.2.2 Optical Pulse Injection and Holding Beam 84
3.2.3 Optical Filtering 91
3.2.4 Active Region Modification 96
3.3…Gain Recovery Improvement Techniques in QD-SOAs 99
3.3.1 Two-Photon Absorption-Assisted Recovery 99
3.3.2 Control Pulse-Assisted Recovery 103
References 113
4 Applications and Functionalities 117
4.1…Introduction 117
4.2…SOA-MZI Gate 118
4.3…SOA-MZI Transfer Function 120
4.4…Michelson Interferometer 122
4.5…Wavelength Conversion 122
4.5.1 XGM-Based Wavelength Conversion 122
4.5.2 XPM-Based Wavelength Conversion 124
4.5.3 FWM-Based Wavelength Conversion 125
4.5.4 Wavelength Conversion in SOA-BPF Configuration 126
4.6…All-Optical Regeneration 130
4.7…Logic Gates 134
4.7.1 XOR Gate 134
4.7.2 AND Gate 136
4.7.3 OR Gate 137
4.7.4 NOR Gate 138
4.7.5 XNOR Gate 142
4.7.6 NAND Gate 144
4.7.7 NOT Gate 146
4.8…All-Optical Multiplexing and Demultiplexing 146
4.8.1 SOA-MZI-Based Multiplexing 147
4.8.2 SOA-MZI-Based Demultiplexing 149
4.9…Data Format Conversion 152
4.9.1 NRZ-to-RZ Data Format Conversion 152
4.9.2 NRZ-to-PRZ Data Format Conversion 154
4.9.3 RZ-to-NRZ Data Format Conversion 156
4.10…All-Optical Flip-Flop 157
4.11…All-Optical PRBS Generation 161
4.12…All-Optical Clock Recovery 163
References 167
5 Application of SOA-Based Circuits in All-Optical Signal Processing and Switching 170
5.1…Introduction 170
5.2…All-Optical Header/Payload Separation 170
5.3…All-Optical Correlator 172
5.4…All-Optical Packet Routing 177
5.5…All-Optical Header Processing 179
5.6…All-Optical Packet Switching Based on In-Band Filtering 182
5.7…All-Optical Self-Routing Node and Network Architecture 184
References 189