Principles of Terahertz Science and Technology

Contents......Page 8
1.1 Terahertz Band......Page 12
1.2.1 Terahertz Sources......Page 14
1.2.2 Terahertz Detectors......Page 16
1.3 Terahertz Applications......Page 18
2.1 Electromagnetic Waves in Matter......Page 21
2.1.1 The Wave Equation......Page 22
2.1.2 Reflection and Transmission......Page 24
2.1.3 Coherent Transmission Spectroscopy......Page 27
2.1.4 Absorption and Dispersion......Page 29
2.1.6 Electric Dipole Radiation......Page 31
2.1.7 Quasi-Optical Propagation in Free Space......Page 34
2.2.1 Quantum Theory of Electric Dipole Interaction......Page 38
2.2.2 Energy Levels of Hydrogen-like Atoms......Page 44
2.2.3 Rotational and Vibrational Modes of Molecules......Page 46
2.2.4 Lattice Vibrations......Page 53
2.3 Laser Basics......Page 57
3.1.1 Optical Pulse Propagation in Linear and Dispersive Media......Page 61
3.1.2 Femtosecond Lasers......Page 64
3.1.3 Time-resolved Pump-Probe Technique......Page 68
3.2.1 Photoconductive Antenna......Page 69
3.2.2 Generation of Terahertz Pulses from Biased Photoconductive Antennas......Page 71
3.2.3 Substrate Lenses: Collimating Lens and Hyper- Hemispherical Lens......Page 77
3.2.4 Terahertz Radiation from Large-Aperture Photoconductive Emitters......Page 80
3.2.5 Time-Resolved Terahertz Field Measurements with Photoconductive Antennas......Page 84
3.3 Optical Rectification......Page 86
3.3.1 Nonlinear Optical Interactions with Noncentrosymmetric Media......Page 87
3.3.2 Second-Order Nonlinear Polarization and Susceptibility Tensor......Page 90
3.3.3 Wave Equation for Optical Rectification......Page 94
3.3.4 Dispersion at Optical and Terahertz Frequencies......Page 97
3.3.5 Absorption of Electro-Optic Crystals at the Terahertz Frequencies......Page 100
3.4 Free-Space Electro-Optic Sampling......Page 102
3.5.1 Optical Rectification and Electro-Optic Sampling......Page 108
3.5.2 Photoconductive Antennas......Page 111
3.6 Terahertz Radiation from Electron Accelerators......Page 113
3.7.1 Phase-Matching with Tilted Optical Pulses in Lithium Niobate......Page 116
3.7.2 Terahertz Generation in Air......Page 118
3.7.3 Narrowband Terahertz Generation in Quasi-Phase- Matching Crystals......Page 119
3.7.4 Terahertz Pulse Shaping......Page 122
4.1 Photomixing......Page 127
4.2 Difference Frequency Generation and Parametric Amplification......Page 132
4.2.1 Principles of Difference Frequency Generation......Page 133
4.2.2 Difference Frequency Generation with Two Pump Beams......Page 135
4.2.3 Optical Parametric Amplification......Page 139
4.3 Far-Infrared Gas Lasers......Page 142
4.4 P-Type Germanium Lasers......Page 143
4.5 Frequency Multiplication of Microwaves......Page 146
4.6 Quantum Cascade Lasers......Page 148
4.6.1 Lasing and Cascading......Page 149
4.6.2 Prospective Development......Page 150
4.7 Backward Wave Oscillators......Page 151
4.8.1 Operational Principles......Page 154
4.9 Thermal Detectors......Page 156
4.9.1 Bolometers......Page 157
4.9.2 Pyroelectric Detectors......Page 161
4.9.3 Golay Cells......Page 164
4.10 Heterodyne Receivers......Page 165
5.1 Dielectric Properties of Solids in the Terahertz Region......Page 168
5.2 Materials for Terahertz Optics......Page 170
5.2.1 Polymers......Page 171
5.2.2 Dielectrics and Semiconductors......Page 173
5.2.3 Conductors......Page 177
5.3.1 Focusing Elements......Page 179
5.3.2 Antireflection Coatings......Page 180
5.3.3 Bandpass Filters......Page 181
5.3.4 Polarizers......Page 183
5.3.5 Wave Plates......Page 184
5.4.1 Theory of Rectangular Waveguides......Page 186
5.4.2 Hollow Metallic Tubes......Page 188
5.4.3 Dielectric Fibers......Page 190
5.4.4 Parallel Metal Plates......Page 192
5.4.5 Metal Wires......Page 193
5.5.1 Metamaterials......Page 198
5.5.2 Photonic Crystals......Page 203
5.5.3 Plasmonics......Page 211
5.6 Terahertz Phonon-Polaritons......Page 220
6.1 Manipulation of Rydberg Atoms......Page 224
6.2.1 Basics of Rotational Transitions......Page 229
6.2.2 High-Resolution Spectroscopy......Page 231
6.2.3 Atmospheric and Astronomical Spectroscopy......Page 233
6.3 Biological Molecules......Page 241
6.3.1 Liquid Water......Page 242
6.3.2 Normal Modes of Small Biomolecules......Page 245
6.3.3 Dynamics of Large Molecules......Page 257
7.1 Introduction......Page 268
7.2.1 Amplitude and Phase Imaging......Page 270
7.2.2 Real-Time 2-D Imaging......Page 273
7.2.3 T-Ray Tomography......Page 275
7.3 Imaging with Continuous-Wave THz Radiation......Page 282
7.3.1 Raster-Scan Imaging......Page 283
7.3.2 Real-Time Imaging with a Microbolometer Camera......Page 287
7.4 Millimeter-Wave Imaging for Security......Page 290
7.4.1 Active Imaging......Page 291
7.4.2 Passive Imaging......Page 293
7.5.1 Optical Properties of Human Tissue......Page 297
7.5.2 Cancer Diagnostics......Page 298
7.5.3 Reflective Imaging of Skin Burns......Page 301
7.5.4 Detection of Dental Caries......Page 303
8.1 Intraband Transitions in Semiconductors......Page 304
8.1.1 Band Structure of Intrinsic Semiconductors......Page 305
8.1.2 Photocarrier Dynamics......Page 306
8.1.3 Impurity States......Page 308
8.1.4 Semiconductor Nanostructures: Quantum Wells, Quantum Wires, and Quantum Dots......Page 311
8.2 Strongly Correlated Electron Systems......Page 320
8.2.1 Quasiparticle Dynamics in Conventional Superconductors......Page 321
8.2.2 Low Energy Excitations in High Temperature Superconductors......Page 326
References......Page 336
F......Page 345
P......Page 346
V......Page 347
Z......Page 348