The combination of optical detection system with a scanning tunneling microscope (STM) leads to the possibility of resolving radiative transition probability with the ultrahigh spatial resolution of STM in real space. This opens an innovative approach toward revealing the correlation between molecular structure, electronic characteristics, and optical properties. This thesis describes a series of experiments that manifests this correlation, including atomic silver chains and single porphine molecules. In atomic silver chains, the number and positions of the emission maxima in the photon images match the nodes in the dI/dV images of "particle-in-a-box" states. This surprising correlation between the emission maxima and nodes in the density of states is a manifestation of Fermi's golden rule in real space for radiative transitions, which provides an understanding of the mechanism of STM induced light emission. From single porphine molecules, orthogonal spatial contrast of two types of vibronic coupling is resolved by both photon spectroscopy and vibronic-mode-selected photon images. Intramolecular transitions from the two orthogonal LUMOs individually couple to different molecular normal modes. This is the first demonstration of the photon emission probability of a single molecule and its direct correlations with the molecular orbitals. This also provides the first real space experimental evidence to separate the tangled effects of molecular conformations and nano-environments on the inhomogeneity of molecular emission. DSB molecules are found to have two conformational isomers and one of them shows surface chirality. All these conformers and enantiomers can be switched to each other by electron injection. Different DSB conformers present distinct manipulation dynamics, which demonstrate how different conformations and their preferred adsorption geometries can have pronounced influence on the molecular mechanics on the surface. Overall, this thesis studies the very fundamental nature of single molecules and artificial nanostructures by integrating all kinds of important functions of STM: topography, spectroscopy, manipulation, and photon emission. Detailed correlations between the emission patterns and orbital structures are revealed by the ultimate spatial resolution of our "STM photon microscopy."

The investigation and manipulation of matter on the atomic scale have been revolutionised by scanning tunnelling microscopy and related scanning probe techniques. This book is the first to provide a clear and comprehensive introduction to this subject. Beginning with the theoretical background of scanning tunnelling microscopy, the design and instrumentation of practical STM and associated systems are described in detail, as are the applications of these techniques in fields such as condensed matter physics, chemistry, biology, and nanotechnology. Containing 350 illustrations, and over 1200 references, this unique book represents an ideal introduction to the subject for final-year undergraduates in physics or materials science. It will also be invaluable to graduate students and researchers in any branch of science where scanning probe techniques are used.

Due to its nondestructive imaging power, scanning tunneling microscopy has found major applications in the fields of physics, chemistry, engineering, and materials science. This book provides a comprehensive treatment of scanning tunneling and atomic force microscopy, with full coverage of the imaging mechanism, instrumentation, and sample applications. The work is the first single-author reference on STM and presents much valuable information previously available only as proceedings or collections of review articles. It contains a 32-page section of remarkable STM images, and is organized as a self-contained work, with all mathematical derivations fully detailed. As a source of background material and current data, the book will be an invaluable resource for all scientists, engineers, and technicians using the imaging abilities of STM and AFM. It may also be used as a textbook in senior-year and graduate level STM courses, and as a supplementary text in surface science, solid-state physics, materials science, microscopy, and quantum mechanics.

I have developed an ultrafast scanning tunneling microscope (USTM) based on uniting stroboscopic methods of ultrafast optics and scanned probe microscopy to obtain nanometer spatial resolution and sub-picosecond temporal resolution. USTM increases the achievable time resolution of a STM by more than 6 orders of magnitude; this should enable exploration of mesoscopic and nanometer size systems on time scales corresponding to the period or decay of fundamental excitations. USTM consists of a photoconductive switch with subpicosecond response time in series with the tip of a STM. An optical pulse from a modelocked laser activates the switch to create a gate for the tunneling current, while a second laser pulse on the sample initiates a dynamic process which affects the tunneling current. By sending a large sequence of identical pulse pairs and measuring the average tunnel current as a function of the relative time delay between the pulses in each pair, one can map the time evolution of the surface process. USTM was used to measure the broadband response of the STM's atomic size tunnel barrier in frequencies from tens to hundreds of GHz. The USTM signal amplitude decays linearly with the tunnel junction conductance, so the spatial resolution of the time-resolved signal is comparable to that of a conventional STM. Geometrical capacitance of the junction does not appear to play an important role in the measurement, but a capacitive effect intimately related to tunneling contributes to the measured signals and may limit the ultimate resolution of the USTM.

Scanning tunneling microscopy (STM) and its extensions have become revolutionary tools in the fields of physics, materials science, chemistry, and biology. These new microscopies have evolved from their beginnings asresearch aids to their current use as commercial tools in the laboratory and on the factory floor. New wonders continue to unfold as STM delivers atomic scale imaging and electrical characterization of the newly emerging nanometer world. This volume in the METHODS OF EXPERIMENTAL PHYSICS Series describes the basics of scanning tunneling microscopy, provides a fundamental theoretical understanding of the technique and a thorough description of the instrumentation, and examines numerous examples and applications. Written by the pioneers of the field, this volume is an essential handbook for researchers and users of STM, as well as a valuable resource for libraries.

A practical introduction to basic theory and contemporary applications across a wide range of research disciplines Over the past two decades, scanning probe microscopies and spectroscopies have gained acceptance as indispensable characterization tools for an array of disciplines. This book provides novices and experienced researchers with a highly accessible treatment of basic theory, alongside detailed examples of current applications of both scanning tunneling and force microscopies and spectroscopies. Like its popular predecessor, Scanning Probe Microscopy and Spectroscopy, Second Edition features contributions from distinguished scientists working in a wide range of specialties at university, commercial, and government research labs around the world. Chapters have been edited for clarity, conciseness, and uniformity of presentation to provide professionals with a concise working reference to scanning probe microscopic and spectroscopic principles, techniques, and practices. This Second Edition has been substantially revised and expanded to reflect important advances and new applications. In addition to numerous examples, the Second Edition features expanded coverage of electrostatic and magnetic force microscopies, near-field optical microscopies, and new applications of buried interfaces in nanomechanics, electrochemistry, and biology. Scanning Probe Microscopy and Spectroscopy, Second Edition is an indispensable working resource for surface scientists, microscopists, and spectroscopists in materials science, chemistry, engineering, biochemistry, physics, and the life sciences. It is also an unparalleled reference text for advanced undergraduates and graduate students in those fields.

Scanning tunneling microscopy (STM) provides three-dimensional real- space images of surfaces at high spatial resolution. When the surface is flat and clean, even atoms can be imaged. Its extreme usefulness has led it to near instantaneous acceptance as a characterization tool. This book covers fundamental concepts of STM operation, image interpretation, instrumentation, and techniques for various applications. It als contains advanced treatments of theory and spectroscopy. Surface physicists, electrochemists, materials scientists, and other scientists who see a use for STM will find the depth of coverage and accompanying reference lists in this book essential to their work. In addition, those who wish to add the capabilities of probe microscopy to their operations, such as microscopists and quality control engineers, will find the basic information in this book.