Preface xi Acknowledgments xvii Part I Basic Concepts 1 1 Ultrafast Dynamics Under Electronic Strong Light-Matter Coupling 3 Courtney DelPo and Gregory Scholes 1.1 Introduction: Energy Levels - Central to Science 3 1.2 Electronic Strong Coupling in Transient Absorption and Reflection Spectroscopy 7 1.2.1 Description of Transient Absorption and Reflection Spectroscopy 7 1.2.2 Polariton Signatures in Transient Absorption and Reflection Spectroscopy 7 1.3 Electronic Strong Coupling in Broadband and Two-dimensional Electronic Spectroscopy 10 1.

4 Electronic Strong Coupling in Applications 11 1.5 Future Outlook of Ultrafast Dynamics in Electronic Strong Coupling 13 References 13 2 Molecular Strong Coupling: The Quantum to Classical Transition 17 William L. Barnes 2.1 Introduction 17 2.2 Interaction Strength and the Bulk Material Response 19 2.3 Comparing Quantum and Classical 24 Acknowledgments 25 References 26 3 The Role of Cavity in Polaritonics: Plasmonic Nanoparticles, Self-hybridized Polaritons, and Casimir Self-assembly 29 Oleg V. Kotov and Timur O. Shegai 3.

1 Plasmonic Resonators 30 3.1.1 Light-Matter Interactions Using Plasmonic Resonators and Their Arrays 30 3.1.2 Single Plasmonic Resonators 33 3.1.3 The Single-emitter Limit 34 3.1.

4 Plexcitonic Photophysics and Photochemistry 37 3.2 Self-hybridized Polaritons 41 3.3 Casimir Microcavities 44 3.4 Conclusions and Outlook 46 References 47 4 Plexciton Photophysics 61 Daniel Finkelstein-Shapiro 4.1 Goal of this Chapter 61 4.2 What is a Plexciton and How Is It Different from a Cavity Polariton 61 4.3 Synthesis of Plexcitons and Their Structure: Influence and Consequence on the Photophysics 64 4.3.

1 Colloidal Systems-based on Organic Molecules 64 4.3.2 Open Cavities 65 4.3.3 Surface Nanocavities 65 4.4 Photophysics of Plexcitons 65 4.4.1 Emitters 66 4.

4.2 Metallic Nanoparticle 67 4.4.3 Plexcitons 69 4.5 Spectral Signatures 73 4.5.1 Suggestions for Approaching Transient Absorption Spectra of Plexcitons 75 4.6 Applications 75 4.

6.1 Photostability 75 4.6.2 Hot Electron Hole Generation 75 4.6.3 Chiral Cavities and Phase Transitions 76 4.7 Conclusion 76 Acknowledgments 76 References 76 5 Coupling of Nanocavities to Molecules 83 Rohit Chikkaraddy and Jeremy Baumberg 5.1 Light and Molecules 83 5.

2 Optical Cavities 85 5.3 Free-electron Model 87 5.4 Introduction to Plasmons 88 5.4.1 Propagating Surface Plasmon Polaritons 90 5.4.2 Localized Surface Plasmon Polaritons 90 5.5 Cavity Description for Plasmon Modes 91 5.

5.1 Qualify Factor 92 5.5.2 Mode Volume 92 5.6 Nanocavities 93 5.6.1 Nanoparticle on Mirror 93 5.6.

2 Sensing Molecules in the Gap 96 5.6.3 Effect of Nanoparticle Size and Shape 96 5.7 Light-Matter Coupling 97 5.7.1 Weak-coupling Regime and Purcell Effect 99 5.7.2 Strong Coupling 103 5.

7.3 Single-molecule Strong Coupling 107 5.8 Conclusion 109 References 109 Part II Spectroscopy and Dynamics 115 6 Nonlinear Spectroscopy Under Vibrational Strong Coupling 117 Adam D. Dunkelberger, Cynthia G. Pyles and Jeffrey C. Owrutsky 6.1 Introduction 117 6.2 Experimental Considerations 120 6.

3 Understanding the Nonlinear Response of MVP 121 6.4 Early Delays 121 6.5 Later Delays 122 6.6 Intermediate Delays 127 6.7 Optical and Photophysical Opportunities 128 6.8 Concluding Remarks 130 Acknowledgments 131 References 131 7 Quantum Dynamics, Optical Signals, and Spectroscopy of Molecular Polaritons 139 Zhedong Zhang 7.1 Introduction 139 7.2 Quantum Electrodynamics of Molecular Polaritons 140 7.

3 Pump-probe Spectra for Molecular Polaritons 143 7.4 Multidimensional Infrared Spectroscopy for Vibrational Polaritons: Density-matrix Theory 144 7.4.1 Gateway-window Formalism 144 7.4.2 Cooperativity Versus Localization 147 7.4.3 Stochastic Model for Vibrational Polaritons 148 7.

4.4 Simulations of 2DIR Spectra for VPs 150 7.5 Multidimensional Electronic Spectroscopy for Exciton Polaritons: Heisenberg-Langevin Theory 154 7.5.1 Langevin Model for Exciton Polaritons 154 7.5.2 Correlation Functions of Vibrations 157 7.5.

3 Absorption Spectrum 158 7.5.4 Time-resolved Emission of Polaritons 159 7.5.5 Two-dimensional Polariton Spectroscopy 159 7.5.6 Connection to Polariton Pump-probe Spectra 162 Acknowledgments 163 References 164 8 Molecular Dynamics Simulations of Exciton-Polaritons in Organic Microcavities 167 Gerrit Groenhof, Ruth H. Tichauer and Ilia Sokolovskii 8.

1 Introduction 167 8.2 Molecular Dynamics in the Collective Strong Coupling Regime 168 8.2.1 Born-Oppenheimer Approximation in the Electronic Strong Coupling Regime 169 8.2.2 Quantum Mechanics/Molecular Mechanics 169 8.2.3 Multiscale Tavis-Cummings Hamiltonian 170 8.

2.4 Multimode Fabry-Pérot Cavities 172 8.2.5 Semiclassical Molecular Dynamics 174 8.3 Applications 177 8.3.1 Polariton Relaxation 177 8.3.

2 Polariton Transport 179 8.3.3 Polaritonic Photochemistry 182 8.4 Summary and Outlook 185 References 185 9 Disorder in Cavity-modified Transport and Chemistry 193 David Hagenmüller, Jérôme Dubail, Francesco Mattiotti, Guido Pupillo and Johannes Schachenmayer 9.1 Introduction 193 9.2 Semilocalization 194 9.2.1 The Disordered TC Model with Hopping 195 9.

2.2 Arrowhead Matrix Model and Dark State Multifractality 199 9.3 The Influence of Disorder and Semilocalization on Vibrational Dynamics 203 9.3.1 The Holstein-Tavis-Cummings Model 203 9.3.2 Vibrational Entanglement and Numerical Simulations 205 9.3.

3 Dynamics After Photo-excitation 207 9.4 Conclusion and Outlook 211 References 213 Part III Applications 219 10 Engineering Organic Exciton-Polariton Condensates in Microcavities 221 Sitakanta Satapathy and Vinod M. Menon 10.1 Introduction 221 10.2 Mechanism of Polariton Condensation in Organic Microcavities 223 10.2.1 Radiative Pumping 224 10.2.

2 Vibron-assisted Relaxation 225 10.3 Experimental Signatures of Polariton Condensation in Organic Microcavities 225 10.4 The Molecular Medley for Polariton Condensation 227 10.4.1 Single Crystalline Systems 227 10.4.2 Low Molecular Weight Emitters 230 10.4.

3 Polymers 235 10.4.4 Host-Guest Systems 238 10.5 Summary 242 References 243 11 Kinetic Models for Polariton Relaxation in Organic Microcavities and Comparison to Experiments 247 Tomohiro Ishii, Stéphane Kéna-Cohen, Felipe Herrera and Chihaya Adachi 11.1 Introduction 247 11.2 Modeling Polariton Kinetics in the Linear and Nonlinear Regime 249 11.2.1 Polariton Kinetics in the Linear Regime 249 11.

2.2 Polariton Kinetics in the Nonlinear Regime 254 11.3 Polariton Relaxation Mechanisms 257 11.3.1 Radiative Pumping Process (1): Initial Experiments 257 11.3.2 Radiative Relaxation 260 11.3.

3 Nonradiative Relaxation 262 11.4 Comparison Between the Experimentally and Theoretically Estimated W ep in BSBCz-EH System 264 11.5 Conclusion 265 References 265 12 Reactions and Assembly Under Vibrational Strong Coupling 271 Kenji Hirai and Hirohi Uji-i 12.1 Introduction 271 12.2 Vibrational Strong Coupling 272 12.3 Chemical Reactions Under VSC 275 12.3.1 Organic Reactions 276 12.

3.2 Enzymatic Reactions Under VSC 280 12.3.3 Symmetry of Molecular Vibrations 281 12.3.4 Interpretation of Vibrational Strong Coupling 281 12.3.5 Self-assembly and Crystallization Under VSC 282 12.

4 Summary 283 References 283 13 Controlling and Probing Molecular Polaritons 289 Michael A. Michon and Blake S. Simpkins 13.1 Introduction 289 13.2 Analytical Description of Cavities 289 13.2.1 Treatment of Lossless Mirrors Bounding an Absorbing Medium 289 13.2.

2 Semiclassical Coupled Oscillators 293 13.3 Nonidealities: That We Must, Nevertheless, Deal with 294 13.3.1 Details for Dealing with Cavities 294 13.3.2 Spatially Dependent Response 296 13.3.3 Line Broadening 298 13.

4 Current Challenges and Proposed Best Practices 299 13.4.1 Current Challenges 300 13.4.2 Measuring Reaction Rates in Optical Cavities 301 13.4.3 Validating Angle-independent Rate Extraction 303 13.4.

4 Proposed Cavity System Design 307 13.5 Conclusion 311 References 311 Part IV Frontiers 315 14 A Comparison of Coulomb and Multipolar Gauge Theories of Cavity Quantum Electrodynamics 317 Adam Stokes and Ahsan Nazir 14.1 Introduction 317 14.2 Perfect Cavity 318 14.2.1 Empty Fabry-Pérot Cavity 318 14.2.2 Perfect Cavity Containing Matter 319 14.

3 Gauge Relativity 324 14.3.1 Relativity and Invariance 324 14.3.2 Gauge Nonrelativistic Predictions 325 14.3.3 A Case Study in Gauge Relativity and Gauge Ambiguities: Dipolar Photon Emission and Detection 329 14.4.