The last decade witnessed significant progress in angle-resolved photoemission spectroscopy (ARPES) and its applications. Today, ARPES experiments with 2-meV energy resolution and $0.2\ifmmode^\circ\else\textdegree\fi{}$ angular resolution are a reality even for photoemission on solids. These technological advances and the improved sample quality have enabled ARPES to emerge as a leading tool in the investigation of the high-${T}_{c}$ superconductors. This paper reviews the most recent ARPES results on the cuprate superconductors and their insulating parent and sister compounds, with the purpose of providing an updated summary of the extensive literature. The low-energy excitations are discussed with emphasis on some of the most relevant issues, such as the Fermi surface and remnant Fermi surface, the superconducting gap, the pseudogap and $d$-wave-like dispersion, evidence of electronic inhomogeneity and nanoscale phase separation, the emergence of coherent quasiparticles through the superconducting transition, and many-body effects in the one-particle spectral function due to the interaction of the charge with magnetic and/or lattice degrees of freedom. Given the dynamic nature of the field, we chose to focus mainly on reviewing the experimental data, as on the experimental side a general consensus has been reached, whereas interpretations and related theoretical models can vary significantly. The first part of the paper introduces photoemission spectroscopy in the context of strongly interacting systems, along with an update on the state-of-the-art instrumentation. The second part provides an overview of the scientific issues relevant to the investigation of the low-energy electronic structure by ARPES. The rest of the paper is devoted to the experimental results from the cuprates, and the discussion is organized along conceptual lines: normal-state electronic structure, interlayer interaction, superconducting gap, coherent superconducting peak, pseudogap, electron self-energy, and collective modes. Within each topic, ARPES data from the various copper oxides are presented.

https://arxiv.org/pdf/cond-mat/0208504.pdf

Angle-resolved photoemission studies of the cuprate superconductors

The physical interaction of gases with crystalline solids: I. Gas-solid energies and properties of isolated adsorbed atoms☆

Recent developments in methods and instrumentation have contributed to major advances in our understanding of the fine structure of amylose and amylopectin. The structure of the starch granule slowly unravels with new insight into key structural features. Following a brief presentation of the structural features common to all starches, the most recent findings for the structure of amylose and amylopectin are reported. The organization of different types of chains in amylopectin is discussed with a critical review of the 'cluster' model leading to the presentation of alternative models. The locations of molecular components in the starch granule are described according to a progress structural order. The description of the crystalline components is followed by a presentation of their supramolecular arrangements. The crystalline components comprise platelet nanocrystals which have already been identified and characterized, and other less well characterized 'blocklet components'. The location and state of amylose within the granule is also presented. This comprehensive review aims at distinguishing between those structural features that have received widespread acceptance and those that are still under debate, with the ambition of being educational and to provide stimulation for further fundamental investigation into the starch granule as a macromolecular assembly.

The molecular structures of starch components and their contribution to the architecture of starch granules: A comprehensive review

Interaction of hydrogen with solid surfaces

Electron transmission through molecules and molecular interfaces has been a subject of intensive research due to recent interest in electron-transfer phenomena underlying the operation of the scanning-tunneling microscope on one hand, and in the transmission properties of molecular bridges between conducting leads on the other. In these processes, the traditional molecular view of electron transfer between donor and acceptor species gives rise to a novel view of the molecule as a current-carrying conductor, and observables such as electron-transfer rates and yields are replaced by the conductivities, or more generally by current-voltage relationships, in molecular junctions. Such investigations of electrical junctions, in which single molecules or small molecular assemblies operate as conductors, constitute a major part of the active field of molecular electronics. In this article I review the current knowledge and understanding of this field, with particular emphasis on theoretical issues. Different approaches to computing the conduction properties of molecules and molecular assemblies are reviewed, and the relationships between them are discussed. Following a detailed discussion of static-junctions models, a review of our current understanding of the role played by inelastic processes, dephasing and thermal-relaxation effects is provided. The most important molecular environment for electron transfer and transmission is water, and our current theoretical understanding of electron transmission through water layers is reviewed. Finally, a brief discussion of overbarrier transmission, exemplified by photoemission through adsorbed molecular layers or low-energy electron transmission through such layers, is provided. Similarities and differences between the different systems studied are discussed.

http://atto.tau.ac.il/~nitzan/anrev-published.pdf

Electron transmission through molecules and molecular interfaces

A characteristic switching time, associated with an impurity embedded in a tight-binding polyene chain, is developed. The modulated-energy traversal time, derived for potential models, is modified to the tight-binding situation. Since the traversal time takes into account the physical distance propagated, which is a meaningless concept in the context of the tight-binding model, we obtain an interaction time that measures the delay in tunnelling through the impurity site. The switching time is discussed in terms of the impurity-parameter space. \textcopyright{} 1996 The American Physical Society.

Tight-binding study of interaction time in molecular switches

Formula for thermal accommodation coefficient as basis for accommodation coefficient of monatomic gas-solid system calculation

Formula for thermal accommodation coefficients.

We present a calculation of the attractive (van ver Waals) forces that are to be expected between tips and samples in experiments using atomic-force microscopes and scanning tunneling microscopes, and we discuss the important roles that these attractive forces, and their repulsive counterparts, play in the experiments. It is shown that the attractive forces have been underestimated in previous work, and we discuss important consequences of this fact. For example, we conclude that atomic-force microscopes should be operated with their tips touching the surface, but with their cantilevers deflected towards the surface so that the associated spring forces counteract most of the attractive forces. Further, we suggest that these microscopes may operate more satisfactorily in liquid environments because of the resulting reduction in the attractive forces.

Roles of the attractive and repulsive forces in atomic-force microscopy

We propose a simple, parameter-free two-fluid model for the collective electron response of a single-walled carbon nanotube, which treats the s and p electrons as separate two-dimensional fluids constrained to the same cylindrical surface. The electrostatic interaction between the fluids gives rise to splitting of the plasmon frequencies into two groups closely following the experimentally determined longitudinal dispersions of the s +p and p plasmons. The model is used to calculate the induced electron density on the nanotube, as well as the stopping power for a charged particle moving parallel to the axis of the nanotube. It is found that these quantities exhibit novel features when the particle speed matches the phase velocity of the quasiacoustic p plasmon.

/pdf/interactions-of-fast-ions-with-carbon-nanotubes-two-fluid-344d4i8kfm.pdf

Frank O. Goodman

Papers

Tight-binding study of interaction time in molecular switches

Formula for thermal accommodation coefficients.

Roles of the attractive and repulsive forces in atomic-force microscopy

Interactions of fast ions with carbon nanotubes: Two-fluid model

Quantum-mechanical treatment of the one-phonon inelastic scattering of gas atoms in three dimensions by a simplified continuum model of a solid