Anders Flodström

EIT Digital, IVZW, Brussel Belgium · Head Office

The EU has 500 million citizens, and is the largest economy in the world. Still, Europe is not a global leader in innovation. In 2008, the European Parliament founded the EIT (European Institute of Innovation and Technology), to answer the need to increase Europe’s competitiveness on the global market. EIT was created also to make new education hap...

Your Editorial “Promoting women in science and medicine” (Nov 20, p 1712)1 is timely. The genSET science leaders panel2 analysed gender and sex bias in basic research and found that medical treatments for women are less evidence-based than for men. Pain research demonstrates this point well: 79% of animal studies published in the journal Pain over...

Switching from superconducting (S) to normal (N) state was investigated using short rise time (∼ 10−10 s) electric pulses in MBE grown Bi-Sr-Ca-Cu-O and rf magnetron sputtered Y-Ba-Cu-O submicron thickness microstrips. It was found that two reversible processes: fast electronic (τ∼10∼−12 s) and slow thermal (τ∼10∼−8s) one take place during switchin...

A review of synchrotron radiation excited photoemission experiments on semiconductor surfaces is given. We stress the importance of angle resolved photoemission experiments using synchrotron radiation to study the surface and bulk electronic structure of semiconductors. Recent progress to use excitations to energy regions, where calculated non free...

Synchrotron radiation (15 h? 75 eV) has been used to study ion desorption from water and methanol adsorbed on a Ti(0001) surface, in an effort to understand ion desorption from covalently bonded systems. Both water and methanol dissociate at all coverages upon adsorption on Ti at 300 K. Using variable wavelength UPS, the adsorbed fragments OH, O an...

A review is presented of a series of electron spectroscopic measurements investigating the surface properties of aluminum by its interaction with molecular oxygen. The studies performed at the Stanford Synchrotron Radiation Laboratory have used the unique properties of synchrotron radiation. The tunability of the excitation source in the spectral r...

Al(111) has been studied with angle-resolved photoelectron spectroscopy. A previously not observed surface state band located around the K point in the surface Brillouin zone is reported. The measured dispersion of the surface state band falls in an absolute electron energy band gap when the three-dimensional band structure from a new LAPW (Lineari...

Synchrotron radiation excited photoelectron spectra of the 4f emission region for all lanthanide metals Ce58 to Lu71 (except Pm61) have been recorded. Photon energies ranging from 30 eV to 200 eV have been used to excite the 4f electrons with maximum surface sensitivity. The 4f emission spectra of all metals studied, with the exception of Ce, show...

The surface free energy (SFE) of (1×1)-surfaces of crystals, without reconstruction and adsorption, is calculated using a bond-broken mode. In the mode, the potential energy of the crystals is treated as a sum of the energies of the bonds connecting pair-wise atoms (u-bonds). The SFE is calculated based on the bond energy and the area density of da...

Hg–Ba–Ca–Cu–O thin films prepared on SrTiO3 (100) substrates generally exhibit shorter c-axis unit cell lengths and lower zero-resistance superconducting transition temperatures as compared to bulk. Microstructural studies of HgBa2CaCu2O6+δ films based on X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) revealed shorter...

The effect of incorporating oxygen and nitrogen into the feed gases on the texture and surface morphology of diamond film synthesized by hot filament chemical vapor deposition (HFCVD) is investigated. The reactant gas composition is determined by the gas flow rates. At a constant flow rate of hydrogen (33sccm) and methane (0.68sccm), the oxygen and...

Results of scanning tunnelling microscopy (STM) show that two different kinds of surface structures coexist on the (110) surface of Pt80Fe20. The predominant structure corresponds well to the missing row type (1*2) reconstruction previously observed on, for example Pt(110), whereas the minority domains show a faintly buckled structure with approxim...

Superconducting Bi2Sr3-xCaxCu2Oy films with x ranging from 1.05 to 2.20 have been prepared using molecular beam epitaxy (MBE) with four metal sources and post-annealing of the evaporated metal mixture films in oxygen and air atmospheres. Annealing in air at 800 degrees C for 1-3 h yields a single-phase state with 2212-like structure for films with...

The influence of electron doping, via deposition of small amounts of Cs, on the electronic structure of has been studied by high-resolution photoelectron spectroscopy (PES) and x-ray absorption spectroscopy (XAS), utilizing synchrotron radiation. The changes in the electronic structure were monitored by PES of the valence band and of the O 1s, Bi 4...

Monophasic samples of seven different oxides with perovskite structure, and also -NaAlO2 have been prepared for catalytic applications. They have been characterized by X-ray diffraction and electron microscopy, then by X-ray photoelectron spectroscopy (XPS). The XPS spectra of LaAlO3, La0.9Sr0.1Al0.8Cu0.1Ru0.1O3, La0.8Sr0.2Al0.8Cu0.1Ru0.1O3 and -Na...

The free energy of a (1×1)-surface, with no relaxation and no adsorption, is calculated using a bond-breaking mode in which the potential energy of the crystal is treated as the sum of the energy of the bonds connecting pair-wise atoms. Based on a purely geometrical model, the number of broken bonds or dangling bonds per atom is calculated on the s...

Superconducting HgBa2CaCu2O6+δ (Hg-1212) thin films have been prepared by laser ablation followed by post-annealing at high temperatures. Two synthesis methods were investigated, using (1) direct reaction of Hg–Ba–Ca–Cu–O precursor films in a Hg-controlled ambience, and (2) thermal diffusion of Hg into Ba–Ca–Cu–O precursor films in a controlled atm...

The reduction of NO, in the presence of i-C4H10or i-C4H8and O2, catalyzed by a platinum foil, was studied in order to understand better the catalytic activity of platinum metal, free of any support or dispersion effects. The reaction products were analyzed by mass spectrometry, and the surface was characterized by X-ray photoelectron spectroscopy a...

Structure and texture of Bi-2212 single-phase and double -phase (Bi-2201+Bi-2212) films and their changes under the thermocycling in the temperature range 77-300 K where studied by X-ray diffraction analysis. Under the thermocycling double-phase film revealed a more perfect texture and stability than the single phase one. It is explained by the fac...

The role of various intergrowth defects acting as charge reservoirs in infinite-layer-structure Ca1-xSrxCuO2 films is widely discussed, while internal structural properties of the CuO2 planes that are important in acquiring the charge have received significantly less attention. We present experimental evidence based on reflection high-energy electr...

Polycrystalline diamond films with surface morphologies of {100} and {111} facets were synthesized using hot filament assisted chemical vapor deposition (HFCVD) from a methane-hydrogen gas mixture. It is found that under the HFCVD conditions, metastable equilibrated growth of diamond crystal can be controlled by changing parameters. In the present...

The microstructure of Bi2Sr2Can-1CunOy multilayers grown by molecular beam epitaxy on atomically flat SrTiO3 substrates has been studied by reflection high-energy electron diffraction (RHEED), atomic force microscopy, and x-ray-diffraction (XRD) techniques. The overall RHEED data, collected in situ at different Bi2Sr2CuOy/Bi2Sr2CaCu2Oy (2201/2212)...

The mechanism of NO reduction on copper in the presence of oxygen and isobutene was studied at T = 770 K, under reducing conditions. Mass spectroscopy was used to identify gas-phase intermediates and reaction products. One intermediate species resulting from the partial oxidation of isobutene was shown to be active in the NO conversion. X-ray photo...

The surface morphology and nucleation of molecular beam epitaxy-grown ‘infinite-layer’ structure, (Sr,Ca)CuO2 films on atomically flat SrTiO3 are studied by reflection high-energy electron diffraction (RHEED) and atomic force microscopy (AFM). The SrTiO3 (100) surfaces were prepared by an ultra-high vacuum (UHV) annealing and displayed regular arra...

The influence of sulfur dioxide on the reduction of nitric oxide over copper, in the presence of isobutene and oxygen, has been examined under reducing conditions in the 720 to 820 K temperature range. The catalytic activity of NO conversion was drastically decreased by the presence of a few ppm of SO2 in the gas phase, and the toxicity of sulfur w...

The formation of thin copper oxide (CuO) films on MgO(100) was studied by reflection high-energy electron diffraction (RHEED) and atomic force microscopy (AFM). The CuO films were grown by molecular beam epitaxy using NO2 as oxidant. For coverages exceeding 3 nm, the RHEED patterns indicate a two-dimensional growth of the CuO films with CuO(111) pl...

Al2O3 has been ablated on commercially available 3 '' silicon wafers at different distances between the target and the substrate and laser fluencies. 'Amorphous' Al2O3 (gamma-alumina with grain size <20 nm) was gown by pulsed laser deposition at room temperature. The structure, the morphology, the profile and the composition of the produced films h...

We show that a small doping of Tl2O3 in the bulk material significantly promotes the formation of superconducting HgBaCaCuO films during encapsulated post-annealing. We also demonstrate that by using this method good quality superconducting HgBa2CaCu2O6+δ films can directly be prepared using Hg-free thin film precursors. As-prepared films display a...

The adsorption of Li on the Si(100) surface has been studied over a wide coverage range with high-resolution core-level spectroscopy. The dimer structure of the clean surface was preserved up to a coverage corresponding to Deltaphi=-1.8 eV. Above this coverage intermixing and silicide growth starts. It is shown that the silicide reaction is control...

The microstructure of molecular beam epitaxy (MBE) grown Bi2Sr2CaCu2Ox films has been studied by reflection high-energy electron diffraction (RHEED), high-resolution electron microscopy (HREM) and X-ray diffraction (XRD). In situ recorded RHEED images of as-grown films show two-dimensional growth, 90° oriented domains (twist domains) and an incomme...

In this high-resolution core-level photoelectron spectroscopy study, the adsorption of lithium on the Si(100)2 × 1 surface has been studied for low Li coverages. The basic dimer reconstruction of the clean surface was preserved up to a coverage corresponding to a work function change of Δφ=−1.8 eV, as indicated by low-energy electron diffraction (L...

Pulsed laser deposition have been adapted for precursor fabrication of Hg-Ba-Ca-Cu-O thin films. The preparation involves a sequential deposition of HgO and Ba2CaCu2Ox thin layers at 200 degree(s)C on MgO and SrTiO3 substrates. Processing parameters were optimized by studying surface morphology of the individual layers and by strict Hg content cont...

The growth and epitaxy of Sn on Ge(111) have been investigated using scanning tunneling microscopy (STM), low energy electron diffraction (LEED) and core level photoelectron spectroscopy for coverages ranging from 0.4 monolayers (ML) to above the critical coverage at 1.6 ML. At the lowest coverage a (√3 × √3)R30° reconstruction is formed at an anne...

Thin films of Bi2(Sr1-xCax)3Cu2Oy grown in situ by molecular-beam epitaxy have been studied by x-ray diffraction. The experimental results were interpreted using a general one-dimensional kinematic x-ray-diffraction model. An accurate determination of the lattice structure and of the distribution of the different atoms on the lattice sites is obtai...

The performance of a scanning photoelectron microscope at the MAX I storage ring in Lund is presented. The microscope utilizes undulator radiation in the energy range 15–150 eV and is comprised of a plane‐grating monochromator with a Kirkpatrick–Baez objective and a gracing incidence ellipsoidal focusing mirror. The instrument with its high photon...

Structural properties of molecular beam epitaxy-grown Bi2Sr2Cu1Oy'Bi2Sr2Ca1Cu2Oy multilayers have been studied by x-ray diffraction. A one-dimensional kinematic x-ray diffraction model has been used to describe the structural quality of the multilayers. Interface roughness, stacking defects and unit cell disorder are obtained by an iterative fittin...

The electronic structure of Bi2Sr2CaCu2O8 and Bi2Sr2CuO6 high-Tc superconductors is investigated by Cu 2p x-ray photoemission spectroscopy and valence-band resonant photoemission at the Cu L3 edge. The data suggest strong correlation effects for the Cu 3d electron states due to a large on-site Coulomb interaction. By means of a simplified cluster-c...

Utilizing monochromatized synchrotron radiation strong photoemission enhancements in the valence-band region and the Cu 3p core level have been measured in the vicinity of the Cu L3 threshold of Bi2Sr2CuO6 and Bi2Sr2CaCu2O8 superconductors. For both the valence-band and the Cu 3p level in both crystals the satellite structures show the strongest en...

Scanning tunneling microscopy was used to study the sputtered and annealed (110) surfaces of Mo3Si and Cr3Si. Both surfaces show extended and atomically flat terraces, but in the case of Mo3Si there is also a uniform distribution of Mo crystallites. This difference in morphology is discussed in terms of different preferential sputtering effects. In...

Thin films of Bi2Sr2Can-1CunOx were grown using a layer-by-layer molecular beam epitaxy technique. The results demonstrate that nearly single-phase highly metastable films with n=4 to 11 can be synthesized both on SrTiO3 and MgO substrates and their physical properties studied. X-ray diffraction data of the films with n=8,9, 10 and 11 are presented...

Voltage(V)-Current(I) characteristics and time response measurements were carried out on laser deposited thin film Y-Ba-Cu-O microstrips, using 3-50 ns duration pulses. Two types of electrical instabilities appearing at currents significantly higher then critical (Ic) were investigated. It was shown that first of them, which takes place during seve...

Highly c-axes oriented 2212-phase films have been synthesized from the BiO1.5-CuO-(SrO,CaO) multilayers and uniform magnetron sputtered amorphous Bi-Sr-Ca-Cu-O precursors using postannealing in air at (700÷850)°C. In situ high temperature XRD studies have been carried out to elucidate mechanisms and kinetics of the two-layer phase formation. High c...

A structure model for the Ge(111)-Au([radical]3 [times] [radical]3 )[ital R]30[degree] surface reconstruction is proposed based on scanning tunneling microscopy (STM) and photoelectron spectroscopy on the Ge 3[ital d] and Au 4[ital f] core lines. The basic unit is a Au[sub 3]Ge molecule binding in one-third of the [ital T][sub 1] substrate sites wi...

Room temperature adsorption of I-2 on the Ge(lll) surface is found to break the initial c(2 x 8) adatom reconstruction as iodine preferentially occupies the on top substrate site, breaks the backbonds between the adatom and the substrate and thus removes the Ge adatoms. As this process continues a c(2 x 4), and modifications thereof, reconstruction...

Different monolayer phases of Sn on Si(111)7 × 7 have been studied by means of scanning tunneling microscopy (STM), core-level photoelectron spectroscopy (XPS), and Rutherford backscattering spectrometry (RBS). The STM results show that reconstructions are obtained for room-temperature deposition of ML of Sn followed by sample annealing in a broad...

Since the origin of surface science noble metal⧸elemental semiconductor couples have been considered as “prototypical” systems. After three decades of research their structural and electronic properties remain an intriguing maze despite recent advances made, especially thanks to the development of the near-field microscopies and the extensive use o...

Diamond films were grown on turbostratic carbon (TC) pregrown on Cu substrates by hot filament chemical vapor deposition. Auger electron spectroscopy, Raman spectroscopy, x‐ray diffraction, infrared absorption spectroscopy, and scanning electron microscopy were used to characterize both the TC and the diamond films. It was shown that the TC films c...

The resistance-vs-current and voltage-vs-current dependences of polycrystalline Y-Ba-Cu-O and Bi-Sr-Ca-Cu-O thin film microstrips are studied by nanosecond electrical pulses. It was found that up to a certain current I _c1( I _c1> I _c) thermal processes do not play any role in the origin of the dissipative state. In t...

In this paper, we present a photoemission study of the interaction of Cu, Ag and Au with clean single-crystal Bi2CaSr2Cu2O8 superconductor surfaces. Both the valence-band and the Bi 5d, O 1s and Sr 3d core levels were monitored for all overlayers. Cu, Ag and Au were deposited as consecutively thicker layers starting with a third of a monolayer and...

Taking advantage of the linear polarisation of synchrotron radiation, the polarisation dependence of the O K and Cu L3 X-ray absorption edges has been compared for in situ cleaved Bi2Sr2CaCu2O8 and Bi2Sr2CuO6 single crystals. The X-ray absorption spectra were measured by means of total electron yield detection. The spectra show for both crystals th...

We have identified the adatom contribution in the Ge 3d core-level spectra from the clean Ge(111)c(2\ifmmode\times\else\texttimes\fi{}8) surface, shifted 0.17 eV to higher binding energy compared to the bulk. This adatom component vanishes in the Ge(111)-Sn(7\ifmmode\times\else\texttimes\fi{}7) surface core-level spectra where Sn occupies the adato...

Scanning tunneling microscopy (STM) has been used to study the Ge(111) surface after submonolayer depositions of Ag. At the lowest coverages a (4×4) reconstruction, with small insets of a (3×1) edge structure, is observed. Based on the STM images we propose a mixed Ag and Ge adatom structure for the (4×4) reconstruction, in which the adatoms have l...

Li-adsorption on the Si(111)7 × 7 surface at room temperature has been studied for different metal coverages with core-level spectroscopy. Four Li-induced components are observed in the Si 2p level at high Li-coverages indicating the formation of four thermodynamically stable phases. It is shown that the reaction between the Li atoms and the Si(111...

Non — stoichiometric thin films Bi-Sr-Ca-Cu-O were produced by Molecular Beam Epitaxy technique from four independent metal sources on MgO substrate and investigated by X-ray diffraction. Structure, texture, phase composition and electric properties of films were studied. Phase composition depends on CuO/(SrO+CaO) ratio and electric resistance — on...

Absorption of Na on single crystals of NiO(1 0 0) at room temperature has been investigated via angle-resolved photoemission spectroscopy and measurements of work-function changes. The drastic changes in the valence band spectra upon Na deposition are assigned to a chemical reaction between Na and O where metallic Ni is left as by-product. At short...

The electronic structure of Ca in the high-temperature superconductor Bi2Sr2CaCu2O8 has been studied by x-ray-absorption spectroscopy and resonant-photoemission at the Ca L2,3 absorption edge. In the x-ray-absorption spectrum no edge structure is seen at the energy corresponding to the Ca 2p3/2 core-level binding energy, in agreement with the very...

Amorphous carbon (a-C:H) films were formed on Cu substrates using a carbide-forming transition metal (Mo, Ta or W) as a catalyst with hot-filament chemical vapour deposition (CVD). This amorphous carbon was transformed into diamond in less than one minute when heated at 1273 K with the hot filaments in a H2-0.3%CH4 atmosphere. During the heating et...

In this paper we present a study of the interaction of Pb with a clean single-crystal Bi2CaSr2Cu2O8 superconductor surface based on photoemission and low-energy electron diffraction (LEED). Deposition of Pb on a Bi2CaSr2Cu2O8 crystal kept at room temperature gives rise to the formation of metallic Bi and oxidized Pb at the interface. This behavior...

Thin superconducting Bi-Sr-Ca-Cu-O films with dominating 2212 structure have been synthesized on MgO substrates by simultaneous evaporation of metallic Bi, Sr, Ca and Cu metals from four independent Knudsen evaporation sources and subsequent postannealing of the prepared metal alloy films in air. The thin film zero resistance temperature, Tc,zero,...

Scanning tunneling microscopy (STM) has been used to study different Sn induced reconstructions on the Ge(111) surface; namely the (7 × 7), (5 × 5) and R30° structures. The first two have been confirmed to be of the dimer adatom stacking faults (DAS) type with adatoms mainly being Sn. The R30° superstructure was found at different Sn depositions. A...

High resolution core-level spectroscopy was utilized to study the clean and NH3 exposed Si(100)2×1 surface. The clean surface exhibits two approximately equal intensity surface core-level components at −0.48 and 0.28 eV binding energy referred to the bulk component. NH3 exposure at 300 K induces two surface core-level components at 0.31 and 0.72 eV...

Scanning tunneling microscopy has been performed on the reconstructed polar surface of substoichiometric VC0.80(111). A mixture of (8×1) and (√3 × √3 )R30° reconstructed areas was found. The (8×1) periodicity could be determined to be the result of a square-lattice surface layer superimposed on the hexagonal substrate. As this square lattice must h...

Various compositions Bi-Sr-Ca-Cu-O thin films having 2212–1 ike structure have been synthesized on MgO substrates using Molecular Beam Epitaxy. Four Knudsen metal sources were utilized to prepare alloy films which were subsequently post annealed in air atmosphere. Quenching of the films from the annealing temperature, 800°C-820°C, increased the sup...

After the discovery that core level binding energies are sensitive to the charge distribution of the valence electrons, core level photoelectron spectroscopy has become one of the main analytical techniques in physics and chemistry. For example, an increase in oxidation number is accompanied by stepwise changes in the core level binding energy. The...

Core-level spectroscopy and valence band photoelectron spectroscopy were used to study H2O adsorption on the Si(100) and Ge(100) surfaces. We find that H2O dissociates into H and OH on both surfaces at 300 K. The H and OH are adsorbed in on top positions on the surface. The OH group is tilted with respect to the surface normal on the Si(100) surfac...

Scanning tunneling microscopy (STM) has been used to determine the surface atomic structure of Si(111)(2√3 ×2 √3 )-Sn. The topographic images show four resolved atoms in each (2 √3 ×2 √3 ) unit cell, and the structure is found to be onefold symmetric. Together with coverage measurements, the STM analysis implies that the reconstructed surface is an...

The formation of the Cu-Bi2CaSr2Cu2O8 interface has been studied by photoelectron spectroscopy using synchrotron radiation. Photon energies in the range 20–1000 eV were utilized in order to probe both the valence band and to monitor chemical changes upon Cu deposition, as revealed by the core-level shifts. A strong chemical reaction between Bi2CaSr...

The adsorption of H2O on Ge(100)2×1 was studied with angle-resolved photoelectron spectroscopy. The surface was exposed to H2O at 160 K. The sample was then heated to 300 K where the measurements were performed. The surface band structure was mapped in the [010] direction. We find six bands that we assign to a surface-adsorbate structure. One band...

High resolution electron energy loss spectroscopy has been used to determine how NH3 adsorbs on the Si(100)2 × 1 surface at 300 K. We find that the NH3 molecules dissociate into NH2 and H on adsorption. Combination bands, overtones and double losses for the SiNH2 group are observed. An anneal to 800 K is sufficient to dissociate the adsorbed NH2 g...

The surface shifts of the Cd 4d and S 2p core levels of the wurtzite CdS(101̄0) surface have been measured. The shifts for the Cd4d and S2p levels were 0.39 and −0.43 eV, respectively. The experimental surface shifts are compared to calculated initial state surface shifts from a simple model due to Mönch. It is found that the reduced Madelung poten...

The growth of thin Bi2Sr2Can−1CunO2n + 4−δ superconducting films have been achieved by Molecular Beam Epitaxy (MBE) deposition of Bi, Cu and followed by a high temperature annealing in an atmosphere of wet oxygen. 1000 Å thick films were deposited on MgO(100) substrates. Film quality, transition between different superconducting phases, and surface...

Thin films of superconducting BiCaSrCuO have been grown by molecular beam epitaxy depositions of Bi, Cu, and CaF 2 /SrF 2 on MgO and SrTiO 3 followed by a high‐temperature oxygen anneal. The films showed a fairly wide transition of 20 K at a T c of 80 K. Residual amounts of fluorine, detected with secondary‐ion mass spectrometry, are believed to ca...

The design of a photoemission microprobe beamline at the MAX laboratory is presented. The beamline will utilize the radiation from a 26 period undulator on the 550‐MeV MAX storage ring. The beamline will be capable of providing about 10¹⁰ photons/s of monochromatized radiation (bandwidth better than 0.25 eV) in the energy rang...

Core‐level spectroscopy and valence‐band photoelectron spectroscopy were used to study the Ge(100)2×1 surface dosed with 0.5–100 L H 2 O at 160 K. It is determined that H 2 O adsorbs molecularly at 160 K and forms ice. The H 2 O molecules dissociate into H and OH radicals on the Ge(100)2×1 surface when the sample is heated to 300 K. A simple adsorp...

Using a reparameterized tight binding model the symmetry resolved charge densities of electronic surface-state bands for the (101̄0) and (112̄0) cleavage faces of CdSe are calculated and compared with photoelectron spectroscopy measurements. This comparison reveals that using the relaxed surface atomic geometries predicted by the model the calculat...

Angle-resolved uv photoelectron spectroscopy has been used to study the electronic structure of cleaved CdTe. Within a direct-transition model, valence-band states on the Γ–(K)–X line are probed in normal emission, yielding the energy of the critical points Γ7 and Γ8 and of the minimum of the spin-orbit-split second valence band. A relativistic aug...

A sp3 tight-binding model for CdTe is constructed and validated by comparison with optical absorption and X-ray photoemission data. The energy minimization method is applied to determine the surface structure of the (110) cleavage face. The predicted surface atomic geometry compares well with that obtained from low-energy electron diffraction inten...

The band structure of surface electronic states on the (101¯0) cleavage surfaces of the wurtzite II-VI semiconductors CdS and CdSe has been studied experimentally. With the use of synchrotron radiation excited angle-resolved ultraviolet photoelectron spectroscopy, the surface electronic band structures have been investigated along the high-symmetry...

The application of angle-resolved photoelectron spectroscopy with synchrotron radiation as the source for excitation is demonstrated to be a powerful technique for determining valence-band dispersions as well as for yielding information on which final states are involved in the process. By recording electron-energy-distribution curves in normal emi...

Metal oxides, in particular those that are highly ionic, are ideal systems for the study of mechanisms of stimulated desorption [1]. Many of these ionic materials are also maximal-valency compounds and are useful for examining the Knotek-Feibelman mechanism of stimulated desorption [2]. MgO is one of the most ionic of these materials and, with the...

We have studied H 2 O adsorption on the Si(100) surface using photoelectron spectroscopy to record Si valence bands and Si 2p core level spectra; and photon stimulated desorption to record Si 2p edge total electron yield and H⁺‐ion yield spectra. We assign the valence‐band H 2 O induced peaks at E B =6.3 and 11.2 eV to the Si–OH and to t...

The conduction-band structures of CdTe(110), CdS(112¯0), and CdSe(112¯0) have been studied using angle-resolved inverse photoelectron spectroscopy. With normally incident electrons substantial parts of the conduction bands have been observed and several critical points determined. The energy positions of these are compared with theoretical predicti...

The adsorption of water on two silicon surfaces [reconstructed planar (100)2×1 and single domain stepped (100)2×1 cut 5° towards (011)] was studied using low‐energy electron diffraction and digital imaging electron stimulated desorption ion angular distributions (ESDIAD) as a function of temperature (145–700 K) and coverage. Water has been shown pr...

First Page of the Article

Core-exciton-induced desorption of ${\mathrm{O}}^{+}$ and ${\mathrm{H}}^{+}$ from MgO(100) and MgO(111) has been observed using photon excitation energies spanning the O K edge. Electron-yield data from partially oxidized Mg implies that these states are localized in the near-surface region. ${\mathrm{O}}^{+}$ and ${\mathrm{H}}^{+}$ desorption resu...

The combination of angle-resolved photoelectron and inverse photoelectron spectroscopy has been used to sutdy the electronic band structure of wurtzite CdSe over a 15-eV-wide energy range. Transitions in the uv region involving valence- and conduction-band states along the Gamma-M line in the hexagonal Brillouin zone are interpreted within a direct...