Surface Properties of Semiconductors and Dynamics of Ionic Crystals, 1971 The Lebedev Physics Institute Series, Vol. 48

Investigation of The Nature of The Dominant Recombination Centers on The Real Surface of Germanium. Yu. F. Novototskii- Vlasov.- I. Electron Processes on the Surface of a Semiconductor.- 1. Surface States.- 2. Surface Conductivity.- 3. Surface Recombination.- II. Investigation Methods.- 1. Field Effect Method.- 2. Measurement of the Surface Recombination Velocity.- 3. Steady-State Photoconductivity Method.- 4. Combined Measurement Method.- 5. Optical System.- 6. Measuring Circuit.- 7. Thermostatting of the Sample.- 8. Heating of the Sample by a Current.- 9. Preparation of the Sample..- 10. Vacuum and Gas Admission System.- III. Experimental Results.- 1. Heating in Vacuum. Polar Molecules.- 2. Effect of Ozone on a Freshly Etched Germanium Surface.- 3. Heating in Vacuum to 650°K.- 4. Effect of Ozone on a “Dehydrated” Surface.- 5. Influence of Water Vapor after Heating above 500°K.- 6. Heating at High Temperatures.- 7. Heating at High Temperatures in Oxygen and Ozone.- IV. Discussion.- 1. Analysis of Experimental Data.- 2. Nature of the Compensating Effect of Water.- 3. Nature of Recombination Centers on Real Surface of Germanium.- Conclusions.- Literature Cited.- Theory of Electromagnetic Wave Absorption in Ideal and Nonideal Ionic Crystal Lattices. V. S. Vinogradov.- I. Review of Work on the Theory of Electromagnetic Wave Absorption by Ideal and Nonideal Crystal Lattices.- 1. Classical and Quantum Theories of Infrared Absorption and Dispersion in an Ideal Ionic Crystal Lattice.- 2. Theories Which Take Account of the Influence of Charged Defects on Electro- magnetic Wave Absorption by a Crystal Lattice.- II. The Hamiltonian and the Equations of Motion. Expression of the Complex Polarizability in Terms of Retarded Green’s Functions.- 1. The Hamiltonian for a Lattice Containing Defects. Properties of Its Coefficients..- 2. Expression for the Complex Polarizability of the Lattice in Terms of Retarded Green’s Functions.- 3. The Phonon Creation and Annihilation Operators. The Hamiltonian and the Polarizability in Terms of These Operators. Equations of Motion for Operators.- III. The Quantum Theory of Infrared Absorption and Dispersion in an Ideal Ionic Lattice.- 1. Equations for the Retarded Green’s Functions.- 2. Solution of the Equations for the Green’s Functions.- 3. Discussion.- IV. Absorption of Microwaves in an Ionic Crystal Lattice Containing Charged Defects.- 1. Equations for the Retarded Green’s Functions.- 2. Solution.of the Equations for the Green’s Functions. Expression for the Imaginary Part of the Complex Polarizability.- 3. Calculation of the Coefficient ?? (vi -i~y).- 4. Calculation of ?j?(vi-yi y-vi)o q(y-vi).- 5. Expressions for the Imaginary Part of the Permittivity in the Case of Point and Linear Charged Defects.- 6. Discussion of the Results. Comparison of Theory and Experiment.- Conclusions.- Appendix A. The form of the Coefficients ?(yy’…y(n))(ii’… i(n))º and ?? (yy’…y(n))(ii’… i(n))º for Forces between Pairs of Ions.- Appendix B. Calculation of the Polarization Vectors w?(k| yj)and the Frequencies ?(yj) for Small |y| in the Isotropic Case.- Appendix C. Applicability of the Born Approximation in Calculating the Scattering of Lattice Waves by Charged Defects.- Literature Cited.- Vibrational Spectra of Strontium, Barium, and Calcium Titanates. V. N. Murzin.- I. Introduction.- 1. Vibrational Spectrum of SrTiO3-Type Crystals.- 2. Features of the Vibrational Spectra of Perovskite Ferroelectrics..- II. Experimental Method.- 1. Spectrophotometer for the Far-Infrared Region.- 2. Method of Measurement in the Submillimeter and Radio Ranges.- 3. Method of Preparation of the Samples.- III. The Spectrum of Normal Modes of Vibration in Crystals of Perovskite Type.- IV. Experimental Results and Their Interpretation.- 1. Transmission and Reflection Spectra.- 2. Determination of the Spectral Variation of the Complex Permittivity. The Vibrational Spectrum of SrTiO3, BaTiO3, and CaTiO3.- 3. Dielectric Dispersion of SrTiO3, BaTiO3, and CaTiO3 Polycrystals over a Wide Frequency Range.- 4. Temperature Variation of the Vibrational Spectrum of BaTiO3.- V. Vibrational Spectra of Some Crystals Having Near-Perovskite Structure.- VI. Derivation of the Dispersion Relation and Some Microscopic Properties of BaTiO3.- Conclusions.- Appendix. Determination of the Symmetry Coefficients from the Known Transformation Matrices.- Literature Cited.