D. Dragoman M. Dragoman Optical Characterization of Solids With 184 Figures Springer
1. Elementary Excitations in Solids 1 1.1 Energy Band Structure in Crystalline Materials 2 1.2 k p Method 11 1.3 Numerical Methods of Electron Energy Band Calculation 14 1.4 Phonons 16 1.4.1 Bose-Einstein Statistics 19 1.4.2 Fermi-Dirac Statistics 19 1.5 Plasmons 20 1.6 Magnetic Excitations 22 1.6.1 Magnons.-. 24 1.7 Excitons 26 1.7.1 Frenkel Excitons 26 1.7.2 Wannier-Mott Excitons 27 1.7.3 Interactions Between Excitons 30 1.7.4 Bound Excitons and Excitonic Complexes 31 1.8 Polarons 31 1.9 Polaritons 35 References 36 2. Optica! Transitions 37 2.1 The Quantization of the Electromagnetic Radiation 37 2.2 Transition Probabilities 39 2.2.1 Optical Properties of Crystalline Materials 42 2.2.2 Mechanisms for Spectral Line Broadening 44 2.2.2.1 Lorentzian Broadening of Spectral Lines 44 2.2.2.2 Gaussian Broadening of Spectral Line 45 2.2.2.3 Voigt Profile 46 2.2.3 Multipolar Contributions to the Interaction Hamiltonian 46 2.3 Optical Constants of Solids 47 2.3.1 Kramers-Krönig Relations 50 2.3.2 Drude-Lorentz Theory of the Electrically Charged Oscillators 51 2.3.3 SumRule 54
XII 2.3.4 Microscopic Origin of Absorption 55 2.3.5 Absorption Mechanisms 56 2.3.5.1 Band-to-Band Light Absorption: Direct andaüowed Absorption 56 2.3.5.2 Band-to-Band Direct, Forbidden Transitions 57 2.3.5.3 Band-to-Band Indirect, Allowed Transitions 57 2.3.5.4 Band-to-Band Indirect, Forbidden Transitions 58 2.3.5.5 Effects That Can Appear at Band-to-Band Absorption 59 2.3.5.6 Intraband Absorption 60 2.3.5.7 Absorption on Free Carriers 61 2.3.5.8 Absorption on Wannier-Mott Excitons 62 2.3.5.9 Indirect Excitonic Absorption 63 2.3.5.10 Biexciton Production Through Photon Absorption... 64 2.3.5.11 Light Absorption on Phonons 65 2.3.6 Optical Properties of Solids in External Magnetic Fields 66 2.3.6.1 Energy Levels in Magnetic Field 66 2.3.6.2 Interaction of Electromagnetic Radiation with a System in a Magnetic Field 67 2.3.6.3 Light Interaction with Metals in Magnetic Field 71 2.3.6.4 Phenomena at Low Frequencies 73 2.3.6.5 The Shubnikov-de Haas Effect 75 2.4 Photoluminescence 75 2.5 Inelastic Light Scattering 78 2.5.1 Raman Scattering." 81 2.5.2 Brillouin Scattering 88 2.6 Nonlinear Optical Response of Solids 92 2.6.1 Nonlinear Raman Effect 95 2.6.1.1 Stimulated Raman Effect 95 2.6.1.2 Inverse Raman Scattering 97 2.6.1.3 Hyper-Raman Effect 97 2.6.1.4 Coherent Anti-Stokes Raman Scattering (CARS) 98 2.7 Optical Methods for the Characterization of Light-Matter Interaction 99 2.7.1 Transmission/Reflection Spectroscopy 101 2.7.2 Modulated Reflectance and Transmittance 103 2.7.3 Pump-Probe Spectroscopy 104 2.7.4 Amplitude and Phase Spectroscopy 105 2.7.5 Photoluminescence 108 2.7.6 Light Scattering 110 2.7.7 Four-Wave Mixing 112 2.7.7.1 Optical Bloch Equations 114 2.7.7.2 Quantum Beats and Polarization Beats 117 2.7.8 Spectral Hole Burning 118
XIII 2.7.9 Fluorescence Line Narrowing 120 2.7.10 Magneto-Optical Kerr Effect 121 2.8 Line Identification 122 References 124 3. Optical Properties of Impurities in Solids 127 3.1 Electronic Structure of Isolated Atoms 127 3.2 Ions in Crystals 129 3.3 Frank-Condon Principle for Defects with Large Orbits 137 3.4 Jahn-Teller Effect 138 3.5 Interactions Between Ions 138 3.6 Spatial Migration 142 3.7 Optical Properties of the Rare-Earth Ions 143 3.7.1 Judd-Ofelt Theory of One and Two Photon Transitions 144 3.7.2 Optical Spectraof Rare-Earth Ions 146 3.7.3 Interaction Processes for Rare-Earth Ions 153 3.8 Transition Metal Ions 154 3.8.1 Optical Properties of Transition Metal Ions 155 3.8.2 Iron-Group Ion Pairs 158 3.9 Diluted Magnetic Semiconductors 158 3.10 Manganites 165 3.11 Color Centers 167 3.12 Filled-Shell Ions 169 3.13 Optical Properties of Donors and Acceptors in Semiconductors 170 References - 177 4. Bulk Materials 181 4.1 Electronic Structure 181 4.2 Excitons in Bulk Semiconductors 186 4.3 Anharmonic Effects 190 4.4 Isotope Effects 192 4.5 Effects Due to Alloying 193 4.6 Deformation Potentials 194 4.7 Optical Determination of Magnetic Properties 196 4.8 Rotational Spectraof Solids 199 4.9 Many-Body Effects 200 4.10 Coupled Excitations 202 4.11 Relaxation Phenomena in Bulk Semiconductors 205 4.11.1 Exciton Relaxation 205 4.11.2 Carrier Relaxation 208 4.11.3 Phonon Relaxation 213 4.12 Optical Properties of Metals 214 4.13 Phase Transitions 220 References 231
XIV 5. Optical Properties of Interfaces and Thin Films 235 5.1 Surface Effects 236 5.2 Thin Films 243 5.2.1 Magnetic Thin Films 246 References 250 6. Low-Dimensional Structures 253 6.1 Low-Dimensional Semiconductor Heterostructures 254 6.1.1 Quantum Well Excitons 261 6.2 Optical Properties of Low-Dimensional Semiconductor Heterostructures 263 6.2.1 Intraband Absorption 263 6.2.2 Excitonic Absorption 266 6.2.3 Luminescence 267 6.2.4 Scattering in Low-Dimensional Heterostructures 268 6.2.5 Intersubband Optical Transitions 269 6.2.6 Depolarization Shift and Coulomb Renormalization 270 6.2.7 Radiative Intraband Transitions in Heterostructures. M 270 6.2.8 Collective Excitations 271 6.2.9 Nonlinear Optics 272 6.3 Optical Characterization of Low-Dimensional Semiconductor Heterostructures 272 6.3.1 Confinement Effects 272 6.3.2 Optical Determination Electronic Structure Parameters 278 6.3.3 Determination of Internal Electric Fields 286 6.3.4 Diffusion 288 6.3.5 Optical Properties of Excitons 289 6.3.6 Biexcitons 296 6.3.7 Magnetic Properties 298 6.3.8 Collective Excitations 306 6.3.9 Coupled Excitations 307 6.3.10 Quantum Microcavities 308 6.3.11 Relaxation Phenomena in Low Dimensional Structures 311 6.3.12 Many-Body Effects 318 6.3.13 Coupled Quantum Wells 320 6.3.14 Carbon Nanotubes 324 6.4 Optical Properties of Superlattices 325 6.4.1 Band Structure 328 6.4.2 Excitons in Superlattices 336 6.4.3 Other Parameters 340 6.5 Nanoparticles 342 References 347
XV 7. Optical Properties of Disordered Materials 353 7.1 Disordered Alloys 3 54 7.2 Disordered Superlattices 359 7.3 Rough Surfaces 361 7.4 Polycrystalline and Nanocrystalline Materials 362 7.5 Continuous-Network Structures 371 7.6 Optical Properties of Amorphous Materials 371 7.6.1 Theory of Electronic States in Amorphous Semiconductors... 372 7.6.2 General Optical Properties of Amorphous Semiconductors... 374 7.6.3 Tetrahedrally Coordinated Amorphous Semiconductors 380 7.6.4 Chalcogenide Glasses 391 7.6.5 Other Amorphous Materials 401 References 404 ^ 8. Optical Properties of High-Temperature Superconductors 407 8.1 High-Temperature Superconductors 410 8.2 Optical Methods for HTS Investigation 417 8.2.1 Anisotropy of Optical Response 417 8.2.2 Observation of Superconducting Transition 419 8.2.3 Symmetry of Superconducting Gap 422 8.2.4 Non-BCS Behavior 426 8.2.5 BCS-Like Behavior 430 8.2.6 HTS Dynamics 430 8.2.7 Pseudogap 431 References 438 Index 441 Index of Materials 447