Persistent Spectral Hole-Burning: Science and Applications, Softcover reprint of the original 1st ed. 1988 Topics in Current Physics Series, Vol. 44

Almost fifteen years have now elapsed since the first observations of per­ sistent spectral hole-burning in inhomogeneously broadened absorption lines in solids. The fact that the spectral shape of an inhomogeneously broadened line can be locally modified for long periods of time has led to a large number of investigations of low-temperature photophysics and photochemistry that would not have been possible otherwise. Using hole­ burning, important information has been obtained about a variety of in­ teractions, including excited-state dephasing processes, host-guest dynam­ ics, proton tunnelling, low-frequency excitation in amorphous hosts, relaxation mechanisms for vibrational modes, photochemical mechanisms at liquid helium temperatures, and external field perturbations. At the same time, the possibility that persistent spectral holes might be used to store digital information has led to the study of materials and configura­ tions for frequency-domain optical storage and related possible applica­ tions. This is the first full-length book on persistent spectral hole-burning. The goal is to provide a broadly based survey of the scientific principles and applications of persistent spectral hole-burning. Since the topic is quite interdisciplinary, the book is intended for researchers, graduate stu­ dents, and advanced undergraduates in the fields of chemical physics, solid-state physics, laser spectroscopy, solid-state photochemistry, and high-performance optical storage and optical processing.

1. Introduction.- 1.1 Fundamental Requirements for Persistent Spectral Hole-Burning.- 1.2 Significance for Science and Applications.- 1.3 Historical Overview and Survey of Mechanisms.- 1.4 Synopsis of the Book.- References.- 2. Basic Principles and Methods of Persistent Spectral Hole-Burning.- 2.1 Background.- 2.2 Homogeneous Spectrum of an Electron-Vibrational Transition.- 2.2.1 Integrated Intensities of Purely Electronic Lines and Phonon Sidebands, Electron-Phonon Interactions and Temperature Dependence.- 2.2.2 Relative Width (Q-factor) of PEL. Peak Intensities.- 2.2.3 Role of Local Modes.- 2.3 Inhomogeneous Broadening of the Vibronic Spectrum.- 2.3.1 Inhomogeneous Broadening of Purely Electronic Lines Inhomogeneous Distribution Function.- 2.3.2 Selectivity of the Spectral Response of an Inhomogeneous Absorption Band.- 2.3.3 Inhomogeneous Distribution Function Under Monochromatic Laser Excitation. Site-Selection Spectroscopy.- 2.4 Persistent Spectral Hole-Burning.- 2.4.1 Burning of Spectral Holes in the Inhomogeneous Distribution Function.- 2.4.2 Early Observations of Persistent Spectral Hole-Burning.- 2.5 Kinetics of Persistent Spectral Hole-Burning.- 2.6 Spectroscopic Applications.- 2.6.1 Homogeneous Zero-Phonon Line Broadening and Dephasing in Crystals.- 2.6.2 Photochemical Hole-Burning in Glassy Matrices.- 2.6.3 Homogeneous Linewidths of Vibronic Transitions and Relaxation.- 2.6.4 Off-Resonance Hole-Burning and Non-Correlation Effects.- 2.6.5 Hole-Burning in the Spectra of Chlorophyll-like Molecules.- 2.7 Special Methods of Hole-Burning and Detection.- 2.7.1 Detection of Holes by Doppler Scanning.- 2.7.2 Holographic Detection of Spectral Holes.- 2.7.3 Creation of Sharp Antiholes.- 2.8 Hole-Burning Time-and-Space-Domain Holography.- 2.8.1 Hole-Burning by Picosecond Pulses.- 2.8.2 Theory of Time-and-Space-Domain Holographic Recording and Playback.- 2.8.3 Experimental Results and Discussion.- 2.9 Concluding Remarks.- References.- 3. Photochemical Hole-Burning in Electronic Transitions.- 3.1 Photochemical, Photophysical, and Spin Hole-Burning.- 3.1.1 Historic Survey.- 3.1.2 Radiation-Induced Saturation Versus Chemical Depletion.- a) Transient Saturation.- b) Chemical Depletion.- 3.1.3 Photochemical Systems and Mechanisms.- 3.2 Spectroscopic Analysis of Hole-Burning Experiments.- 3.2.1 General Remarks.- 3.2.2 Fast Relaxation Processes and Excited State Dephasing.- a) Lineshape Analysis.- b) Temperature Dependence of the “Homogeneous” Linewidth.- 3.2.3 Spectral Diffusion in Glasses.- a) TLS Parameters and Tunnelling Rates.- b) Spectroscopic Parameters.- 3.3 Field Effects in Hole-Burning Spectroscopy.- 3.3.1 Introduction: The Site Memory Function.- 3.3.2 Electric-Field Effects.- a) Stark Effect for Molecules with Inversion Symmetry.- b) Stark Effect for Molecules Without Inversion Symmetry.- 3.3.3 Strain-Field Effects.- References.- 4. Persistent Spectral Hole-Burning in Inorganic Materials.- 4.1 Introduction.- 4.2 Hole-Burning Mechanisms.- 4.3 Color Centers.- 4.4 Rare Earth Compounds.- 4.4.1 Trivalent Rare Earth Ions in Glasses.- 4.4.2 Divalent Rare Earth Ions in Crystals.- a) CaF2:Sm2+.- b) SrF2:Sm2+.- c) BaClF:Sm2+.- 4.5 Transition Metal Ions.- 4.5.1 LiGa5 O8:Co2+.- 4.5.2 Y3Al5O12:Ti3+.- 4.6 Conclusion.- References.- 5. Two-Level-System Relaxation in Amorphous Solids as Probed by Nonphotochemical Hole-Burning in Electronic Transitions.- 5.1 Background.- 5.2 Survey of NPHB Systems.- 5.2.1 Hydrogen-Bonded Crystals.- 5.2.2 Molecules in Amorphous Polyacene Films.- 5.2.3 Molecules in Organic Glasses.- 5.2.4 Molecules in Polymers.- 5.2.5 Rare-Earth Ions in Glasses and Polymers.- 5.3 Optical Linewidths and Dephasing in Amorphous Solids.- 5.3.1 Single-Impurity Single-TLS System Hamiltonian.- 5.3.2 Optical Dephasing due to Off-Diagonal Modulation.- 5.3.3 Recent Experiments.- 5.3.4 New Theories.- 5.3.5 Comparison of Theories and Experimental Data.- 5.3.6 Hole Widths and TLS Relaxation Processes in Organic Systems.- 5.4 Density of States Functions for TLS.- 5.5 Laser-Induced Hole Filling.- 5.5.1 Rhodamine 640 in Poly(vinylalcohol).- 5.5.2 Nd3+ and Pr3+ in Poly(vinylalcohol).- 5.5.3 A Tentative Model for LIHF.- 5.6 Recent Developments.- 5.7 Concluding Remarks.- References.- 6. Persistent Infrared Spectral Hole-Burning for Impurity Vibrational Modes in Solids.- 6.1 Introduction.- 6.1.1 Matrix-Isolated Molecules in Van der Waals and Ionic Solids.- 6.1.2 Persistent IR Hole-Burning in Vibrational Modes.- 6.2 Molecules in Van der Waals Matrices.- 6.2.1 1,2-Difluorethane (DFE).- a) Diode Laser Measurements.- b) CO2 Laser Measurements.- 6.2.2 Interpretation of Persistence.- 6.2.3 Molecular Aggregates of Methyl Nitrite or Methanol.- 6.3 ReO4? in Alkali Halide Crystals.- 6.3.1 Background and Spectroscopic Information.- 6.3.2 Measurements of Relaxation Times T1 and T2.- 6.3.3 Persistent Spectral Holes for ReO4? in Alkali Halides.- a) Summary of Characteristics.- b) Model for the PIRSH Process.- 6.3.4 Persistent Spectral Pegs.- 6.3.5 Ultrasonic Studies of Multiple Ground State Configurations.- 6.3.6 Conclusions on the ReO4? System.- 6.4 Persistent Spectral Hole-Burning for CN? Molecules in Alkali Halide Crystals.- 6.4.1 Background Information on Matrix-Isolated CN?.- 6.4.2 High-Resolution FTIR Spectroscopy in the CN? Stretch Region.- 6.4.3 Hole-Burning in the CN? Stretch Mode Region.- 6.4.4 A Study of the CN?:Na+ Center Dynamics.- a) Fluorescence.- b) Hole-Burning and ?l Center Geometry.- 6.4.5 Other CN? Complexes.- 6.5 Conclusion.- 6.5.1 Comparison of the Three Types of Vibrational Hole-Burning Systems.- 6.5.2 Systems Which do not Exhibit PIRSH Formation.- a) Derivatives of the CN? Molecule.- b) Spherical-Top Molecules Which Contain Hydrogen.- 6.5.3 Future Prospects.- a) NO2? in Alkali Halides.- b) Disordered Solids.- References.- 7. Frequency Domain Optical Storage and Other Applications of Persistent Spectral Hole-Burning.- 7.1 Introduction.- 7.2 Systems Issues for Frequency Domain Optical Storage.- 7.2.1 General Remarks.- 7.2.2 Engineering Studies.- 7.3 Materials Research for Frequency Domain Optical Storage.- 7.3.1 General Materials Requirements.- 7.3.2 Limitations of Single-Photon Recording Mechanisms.- 7.3.3 Photon-Gated Mechanisms.- 7.3.4 Limitations on Storage Density.- 7.4 Alternative Data-Storage Configurations.- 7.4.1 Time Domain Storage.- 7.4.2 Electric-Field Readout.- 7.4.3 Holographic Readout.- 7.5 Other Applications of Persistent Spectral Hole-Burning.- 7.5.1 General Remarks.- 7.5.2 Laser Pulse Shaping Based on Fourier Synthesis.- 7.5.3 Laser Pulse Shaping Based on Voltage Modulation.- 7.5.4 Frequency Multiplexed Optical Spatial Filters.- 7.6 Summary and Future Prospects.- References.