ARPES spectroscopy

There is a condition of momentum conservation for photons and electrons which must also be satisfied in the photoemission process. For band electrons, for which the Bloch wavefunctions are characterized by the wavenumber k (proportional to the momentum p of the electron), the momentum conservation condition is important to determine the angular distribution of the photoemitted electrons. Angular J esolved FhotoEmission spectroscopy (ARPES), schematized in Fig. 2, is potentially able to provide, and has been used to obtain, the E(fc) dispersion curves for solids. 

The recent results of angle-resolved photo-electron spectroscopy (ARPES) by A. Lanzara et al. show quite convincingly that the phonons,... 

Angle-Resolved Photoemission. The best experimental technique to resolve the electronic structure of crystals in the momentum-energy space, and, consequently, the Fermi surface, is angle resolved photoemission spectroscopy (ARPES). 

Photoemission. In experiments such as the angular resolved photoemission spectroscopy (ARPES), one has direct access to the momentum and energy dependent one-particle spectral density... 

More detailed information on the specific orbitals involved in bonding of the adlayer and the symmetry of the bonding site can be derived from angle resolved photoemission spectroscopy (ARPES). With excitation energies of less than 20 eV, the incident photons excite predominantly valence electrons. The valence electron resonances observed are characteristic of band structure of the substrate and the electron orbitals of the adspecies, whose energy is... 

A particularly useful variety of UPS is angle-resolved photoelectron spectroscopy (ARPES), also called angle-resolved ultraviolet photoelectron spectroscopy (ARUPS) [, 62]. In this technique, measurements are made of the valence band photoelectrons emitted into a small angle as the electron emission angle or photon energy is varied. This allows for the simultaneous determination of the kinetic energy and momentum of the photoelectrons with respect to the two-dimensional surface Brillouin zone. From this information, the electronic band structure of a single-crystal material can be experimentally determined. 

Acronyms ARUPS (angle resolved ultraviolet photoemission spectroscopy) ARPES (angle resolved photoelectron spectroscopy)... 

Angle resolved ultraviolet photoeiectron spectroscopy (ARUPS) also known as angle resolved photoeiectron spectroscopy (ARPES)... 

Recently, angle-resolved photoemission spectroscopy (ARPES) for Bi2212 showed that the electronic density of states of underdoped cuprates reveals a normal-state gap-... 

From the large number of experimental methods employed currently in the analysis of surfaces (see, e.g., Morrison (1977) and Blakely (1975)), X-ray electron spectroscopy (XES), angle-resolved photoelectron spectroscopy (ARPES) and Auger electron spectroscopy (AES) are the ones which are most widely used for the study of the electronic states of the external layers of refractory phases. Their basic ideas and technical details are described in a number of monographs, see for example Nemoshkalenko et al (1976), Gallon (1981) and Briggs and Sinha (1987). 

In the following sections, progress in studies of the electronic structure of TMC(IOO), (110), and (111) surfaces by the application of angle-resolved photoemission spectroscopy (ARPES) will be reviewed. Adsorption of oxygen and alkali metal on the TMC(IOO) and (111) surfaces will also be reviewed as an example of progress in the surface chemistry of TMCs. 

The electronic structure of the TMC(IOO) surface has been studied most extensively among the low-index TMC surfaces. It is well known that the use of angle-resolved photoemission spectroscopy (ARPES) can give direct information about the valence band structure around the surface (18,19), and extensive ARPES studies have been performed on the valence band structure of TMC(IOO) surfaces such as TiC(lOO) (20,21), ZrC(lOO) (22,23), VC(IOO) (24-27), NbC(lOO) (28-31), and TaC(lOO) (32,33). These studies have shown that most of the features in ARPE spectra can be understood as emissions from the bulk bands, and thus the electronic structures of TMC(IOO) are well regarded as the cross sections of the bulk electronic states. However, in some systems, surface induced electronic states have been identified as described in the following. 

---