Introduction to Metal-Nanoparticle Plasmonics

Based on a popular article in Laser and Photonics Reviews, this book provides an explanation and overview of the techniques used to model, make, and measure metal nanoparticles, detailing results obtained and what they mean. It covers the properties of coupled metal nanoparticles, the nonlinear optical response of metal nanoparticles, and the phenomena that arise when light-emitting materials are coupled to metal nanoparticles. It also provides an overview of key potential applications and offers explanations of computational and experimental techniques giving readers a solid grounding in the field. Acknowledgments ix

Introduction xi

I.1 Why All the Excitement? xi

I.2 Historical Perspective xiv

I.3 Book Outline xvii

1 Modeling: Understanding Metal-Nanoparticle Plasmons 1

1.1 Classical Picture: Solutions of Maxwell’s Equations 2

1.2 Discrete Plasmon Resonances in Particles 13

1.3 Overview of Numerical Methods 25

1.4 A Model System: Gold Nanorods 31

1.5 Size-Dependent Effects in Small Particles 39

References 46

2 Making: Synthesis and Fabrication of Metal Nanoparticles 51

2.1 Top-Down: Lithography 52

2.2 Bottom-Up: Colloidal Synthesis 67

2.3 Self-Assembly and Hybrid Methods 76

2.4 Chemical Assembly 86

References 92

3 Measuring: Characterization of Plasmons in Metal Nanoparticles 97

3.1 Ensemble Optical Measurements 97

3.2 Single-Particle Optical Measurements 102

3.3 Electron Microscopy 125

References 132

4 Coupled Plasmons in Metal Nanoparticles 135

4.1 Pairs of Metal Nanoparticles 136

4.2 Understanding Complex Nanostructures Using Coupled Plasmons 149

References 161

5 Nonlinear Optical Response of Metal Nanoparticles 165

5.1 Review of Optical Nonlinearities 166

5.2 Time-Resolved Spectroscopy 170

5.3 Harmonic Generation 187

References 191

6 Coupling Plasmons in Metal Nanoparticles to Emitters 193

6.1 Plasmon-Modified Emission 193

6.2 Plasmon–Emitter Interactions Beyond Emission Enhancement 210

References 225

7 Some Potential Applications of Plasmonic Metal Nanoparticles 229

7.1 Refractive-Index Sensing and Molecular Detection 229

7.2 Surface-Enhanced Raman Scattering 233

7.3 Near-Field Microscopy, Photolithography, and Data Storage 239

7.4 Photodetectors and Solar Cells 242

7.5 Optical Tweezers 249

7.6 Optical Metamaterials 254

References 266

Index 271

“The present volume will be very useful for graduate students, post-doctoral researchers and advanced undergraduates. The instructors and advisers of such students will benefit from reading this book as well.” (Optics & Photonics News, 8 November 2013)

MATTHEW PELTON, PhD, is a Physicist at the Center for Nanoscale Materials, Argonne National Laboratory, researching the new physical phenomena that arise when light interacts with nanomaterials.

GARNETT BRYANT, PhD, is a Supervisory Physicist at the National Institute of Standards and Technology (NIST) where he is the Group Leader of the Quantum Processes and Metrology Group conducting research on nanosystems and nanophotonics.

From theory to applications, this book provides a thorough introduction to current research in the optical properties of metal nanoparticles

Based on a popular article in Laser & Photonics Reviews, this book provides an explanation and overview of the techniques used to model, make, and measure metal nanoparticles, detailing and interpreting results. It also covers the properties of coupled metal nanoparticles, the nonlinear optical response of metal nanoparticles, and the phenomena that arise when light-emitting materials are coupled to metal nanoparticles.

Emphasizing fundamental physical understanding throughout—and offering explanations of computational and experimental techniques supporting this basic understanding—Introduction to Metal-Nanoparticle Plasmonics gives readers a solid grounding in the field.

Beginning with an introduction that covers the excitement surrounding the topic and the long history behind it, the book then:

• Describes analytical and numerical methods for calculating and understanding plasmon resonances in metal nanoparticles
• Explains top-down lithographic methods and bottom-up chemical methods for fabricating metal nanoparticles and their assemblies
• Illustrates experimental methods for characterizing plasmon resonances in metal nanoparticles
• Covers coupled plasmon resonances in assemblies of metal nanoparticles
• Discusses nonlinear optical properties of metal nanoparticles
• Explains how plasmons in metal nanoparticles can interact with nearby light-emitting material
• Presents a selection of potential applications of plasmons in metal nanoparticles

An ideal introduction to current research in the optical properties of metal nanoparticles, Introduction to Metal-Nanoparticle Plasmonics will appeal to graduate students, postdoctoral researchers, and advanced undergraduate students looking for a deeper scientific understanding of the field.