ANGLE-RESOLVED PHOTOEMISSION STUDIES OF THE 3C–SiC(001)(2×1) SURFACE

We have investigated the electronic structure of the single-domain 3C–SiC(001)(2×1) using angle-resolved photoemission and synchrotron radiation. Two different surface-state bands are clearly identified within the bulk bandgap. The upper band has a binding energy of 1.4 eV at the center of the surface Brillouin zone (SBZ) and shows a weak dispersion of 0.3 eV in the [Formula: see text] direction, but is nondispersive in the perpendicular direction. It has a polarization dependence suggesting a pz character, as expected for a Si dangling-bond state. The second band is located at 2.4 eV binding energy and is nondispersive. The weak or nonexistent dispersions suggest very localized electronic states at the surface and show poor agreement with calculated dispersions for the proposed models for the 2×1 and c(4×2) reconstructions.

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A NEGATIVE SPIN-POLARIZATION STRUCTURE OF Ni(110): PROBED BY SPIN- AND ANGLE-RESOLVED PHOTOELECTRON SPECTROSCOPY

Surface Review and Letters ◽

10.1142/s0218625x02003640 ◽

2002 ◽

Vol 09 (02) ◽

pp. 1287-1290

Author(s):

S. QIAO ◽

A. KIMURA ◽

H. NARITA ◽

K. YAJI ◽

E. KOTANI ◽

...

Keyword(s):

Binding Energy ◽

Spin Polarization ◽

Brillouin Zone ◽

Surface State ◽

Photoelectron Spectroscopy ◽

Text Line ◽

Negative Polarization ◽

Polarization Structure ◽

Surface Brillouin Zone

We already reported the spin- and angle-resolved photoelectron measurements of Ni(110), Ni (110)- p (2 × 1) O and Ni (110)- c (2 × 2) S along the [Formula: see text] line of the Ni(110) surface Brillouin zone using He I radiation. We found that the structure at about 1.3 eV binding energy showed unusual character near the [Formula: see text] point. The spin polarization of this structure was observed to be negative. After the adsorption of oxygen and sulfur on the Ni(110) surface, the degree of negative spin polarization was found to decrease. To study the property of this state, that it is a bulk or surface-related, and to clarify the origin of the negative polarization, we performed spin- and angle-resolved photoemission measurements for Ni(110) along the LW line of its bulk Brillouin zone. The results show that this negative polarization structure can be attributed to a surface state near the [Formula: see text] point.

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SPACE-CHARGE SPECTROSCOPY OF ELECTRONIC STATES IN Ge/Si QUANTUM DOTS WITH TYPE-II BAND ALIGNMENT

International Journal of Nanoscience ◽

10.1142/s0219581x07004511 ◽

2007 ◽

Vol 06 (05) ◽

pp. 353-356

Author(s):

A. I. YAKIMOV ◽

A. V. DVURECHENSKII ◽

A. I. NIKIFOROV ◽

A. A. BLOSHKIN

Keyword(s):

Quantum Dots ◽

Electronic Structure ◽

Binding Energy ◽

Space Charge ◽

Tensile Strain ◽

Electronic States ◽

Band Alignment ◽

Type Ii ◽

Electron Confinement ◽

Si Quantum Dots

Space-charge spectroscopy was employed to study electronic structure in a stack of four layers of Ge quantum dots coherently embedded in an n-type Si (001) matrix. Evidence for an electron confinement in the vicinity of Ge dots was found. From the frequency-dependent measurements the electron binding energy was determined to be ~50 meV, which is consistent with the results of numerical analysis. The data are explained by a modification of the conduction band alignment induced by inhomogeneous tensile strain in Si around the buried Ge dots.

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NEW ELECTRONIC STATES ON CLEAN Si(110)-“16×2” SURFACES

Surface Review and Letters ◽

10.1142/s0218625x95000546 ◽

1995 ◽

Vol 02 (05) ◽

pp. 573-577 ◽

Cited By ~ 5

Author(s):

A. CRICENTI ◽

B. NESTERENKO ◽

P. PERFETTI ◽

G. LE LAY ◽

C. SEBENNE

Keyword(s):

Electronic Properties ◽

Brillouin Zone ◽

Photoelectron Spectroscopy ◽

Structural Model ◽

Electronic States ◽

Surface States ◽

Ultraviolet Photoelectron Spectroscopy ◽

Surface Brillouin Zone ◽

Differential Reflectivity

The electronic properties of a clean Si (110)-“16×2” surface have been studied by angle-resolved ultraviolet photoelectron spectroscopy (ARUPS) and surface differential reflectivity (SDR). Four surface states have been recognized by ARUPS and their dispersions have been mapped along the main symmetry lines in the surface Brillouin zone. SDR experiments revealed transitions between filled and empty surface states at ~ 1.8, 2.4, and 2.9 eV. The results are explained on the basis of a new structural model of the Si (110)-“16×2” phase.

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Orbitals and bands at metal surfaces: photoemission from the {110} surface of tungsten

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1981.0108 ◽

1981 ◽

Vol 376 (1767) ◽

pp. 565-583 ◽

Cited By ~ 13

Keyword(s):

Electronic Structure ◽

Band Structure ◽

Surface State ◽

Photon Emission ◽

Tight Binding ◽

Tight Binding Approximation ◽

The Third ◽

Surface Brillouin Zone ◽

Orbital Character ◽

Bulk Band

The electronic structure of the {110} surface of tungsten has been investigated by using angle-resolved photoemission. A surface state has been identified and characterized throughout the surface Brillouin zone (s. B. z.). Its dispersion is found to correlate with the projected band gap between the third and fourth bands of the tungsten bulk band structure. It is identified by comparison with Inglesfield’s calculation as having predominantly m = 1 d-orbital character. With photon energies of 21.2 and 40.8 eV, intense photoemission from the surface state is only observed after surface Umklapp, whereas, with 16.8 eV, photon emission is observed in both the first and second s. B. zs. The applicability of the tight-binding approximation to the elucidation of the electronic structure of a metal surface is examined with particular reference to this surface state. A qualitative analysis of the observed photoemission intensities is consistent with emission from a tungsten e g orbital that is hybridized with e g orbitals on neighbouring atoms.

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Surface state at theK¯point of the surface Brillouin zone on Cu{111}

Physical Review B ◽

10.1103/physrevb.54.5092 ◽

1996 ◽

Vol 54 (7) ◽

pp. 5092-5096 ◽

Cited By ~ 11

Author(s):

Y. Yang ◽

S. C. Wu ◽

F. Q. Liu ◽

K. Ibrahim ◽

H. J. Qian ◽

...

Keyword(s):

Brillouin Zone ◽

Surface State ◽

Surface Brillouin Zone

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Surface State at Kmacr- Point of Surface Brillouin Zone on Cu{111} Surface

Chinese Physics Letters ◽

10.1088/0256-307x/13/6/018 ◽

1996 ◽

Vol 13 (6) ◽

pp. 465-468

Author(s):

Yi Yang ◽

Feng-qin Liu ◽

Jin-feng Jia ◽

Yu-hui Dong ◽

Kurash Ibrahim ◽

...

Keyword(s):

Brillouin Zone ◽

Surface State ◽

Surface Brillouin Zone

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Photoemission Study of The Electronic Structure of Wurtzite Gan(0001) Surfaces

MRS Proceedings ◽

10.1557/proc-482-787 ◽

1997 ◽

Vol 482 ◽

Cited By ~ 4

Author(s):

Kevin E. Smith ◽

Sarnjeet S. Dhesi ◽

Cristian B. Stagarescu ◽

James Downes ◽

D. Doppalapudi ◽

...

Keyword(s):

Electronic Structure ◽

Valence Band ◽

Surface State ◽

High Vacuum ◽

Valence Band Maximum ◽

Ultra High Vacuum ◽

Angle Resolved Photoemission Spectroscopy ◽

Surface Electronic Structure ◽

Bond State ◽

Photoemission Study

AbstractThe surface electronic structure of wurtzite GaN (0001) (1 × 1) has been investigated using angle-resolved photoemission spectroscopy. Surfaces were cleaned by repeated cycles of N2 ion bombardment and annealing in ultra-high vacuum. A well-defined surface state below the top of the valence band is clearly observed. This state is sensitive to the adsorption of both activated H2 and O2, and exists in a projected bulk band gap, below the valence band maximum. The state shows no dispersion perpendicular or parallel to the surface. The symmetry of this surface state is even with respect to the mirror planes of the surface and polarization measurements indicate that it is of spz character, consistent with a dangling bond state.

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The $(\sqrt{3}\times\sqrt{3}){\rm R}30^{\circ}$-Reconstructed 6H–SiC(0001): A Semiconducting Surface

Surface Review and Letters ◽

10.1142/s0218625x98000360 ◽

1998 ◽

Vol 05 (01) ◽

pp. 193-197 ◽

Cited By ~ 17

Author(s):

I. Forbeaux ◽

J.-M. Themlin ◽

V. Langlais ◽

L. M. Yu ◽

H. Belkhir ◽

...

Keyword(s):

Charge Transfer ◽

Fermi Level ◽

Brillouin Zone ◽

Surface State ◽

Photoemission Spectroscopy ◽

Metallic Behavior ◽

Inverse Photoemission ◽

Surface Brillouin Zone ◽

Inverse Photoemission Spectroscopy ◽

Good Agreement

k//-resolved inverse-photoemission spectroscopy of the [Formula: see text] reconstruction of 6H–SiC(0001) reveals a sharp surface state U located 1.10±0.05 eV above the Fermi level at the center of the surface Brillouin zone with a total bandwidth of 0.34±0.05 eV. This value is in good agreement with recent LDA calculations which predict an adatom-induced surface state Σ1 which should be half-filled. In this model, the adatoms are Si atoms occupying the T 4 site above a compact SiC(0001) (Si) termination. In contrast to the predicted metallic behavior, the U state remains completely unoccupied throughout the whole Brillouin zone, and the surface is semiconducting. We propose that some charge transfer from the Si adatoms towards subsituted C atoms in the terminating bilayer stabilizes the reconstruction by moving up the Σ1 state away from the Fermi level.

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Electronic structure of α-sexithiophene ultrathin films grown on

Physical Chemistry Chemical Physics ◽

10.1039/c7cp05222g ◽

2018 ◽

Vol 20 (2) ◽

pp. 1114-1126 ◽

Cited By ~ 1

Author(s):

Shinya Ohno ◽

Hiroya Tanaka ◽

Kazuma Tanaka ◽

Kazutoshi Takahashi ◽

Masatoshi Tanaka

Keyword(s):

Electronic Structure ◽

Synchrotron Radiation ◽

Ultrathin Films ◽

Photoelectron Spectroscopy ◽

Electronic States

We investigated the electronic states of α-sexithiophene (α-6T) on by means of angle-resolved photoelectron spectroscopy using synchrotron radiation.

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Photoelectron Spectra of Gd2O2− and Non-Monotonic Photon-Energy Dependent Variations in Populations of Close-Lying Neutral States

10.26434/chemrxiv.13237307.v1 ◽

2020 ◽

Author(s):

Jarrett L. Mason ◽

Hassan Harb ◽

Ali Abou Taka ◽

Abbey McMahon ◽

Caleb D. Huizenga ◽

...

Keyword(s):

Electronic Structure ◽

Binding Energy ◽

Photon Energy ◽

Valence Electron ◽

Electronic States ◽

Photoelectron Spectra ◽

Antiferromagnetic Coupling ◽

Energy Window ◽

Electron Transitions ◽

Energy Dependent

Photoelectron spectra of Gd2O2− obtained with photon energies from 2.033 eV to 3.495 eV exhibit numerous close-lying neutral states with photon-energy-dependent relative intensities. Transitions to states falling within the electron binding energy window of 0.9 and 1.6 eV are attributed to one- or two-electron transitions to the ground and low-lying excited neutral states. An additional, manifold of electronic states observed in the 2.1 to 2.8 eV window cannot be assigned to any simple one-electron transitions. Because of the relatively simple electronic structure from the half-filled 4f7 subshell occupancy in Gd2O2–, the numerous transitions observed in the spectra are fairly well-resolved, allowing a detailed view of the changes in relative intensities of individual transitions with photon energy. With supporting calculations on the numerous close-lying electronic states, we suggest a description of strong photoelectron-valence electron interactions that result in the photon-energy dependent shake-up transitions and switching between ferro- and antiferromagnetic coupling.

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