Dependence of the optical cross section of interface states on the photon energy at Si-SiO2 structures

ABSTRACTThe constructive interference between direct and indirect channels above the absorption threshold of a core level leads to a massive increase in the emission cross section leading to a phenomenon called “resonant photoemission”. Using novel magnetic linear dichroism in angular distribution photoelectron spectroscopy experiment we have tried to understand the nature of the resonant photoemission process in Gd metal. The presence of dichroism in Gd 4f photoemission intensity at a photon energy corresponding to resonant photoemission clearly demonstrates the photoemission-like nature of the resonant photoemission process.

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The Defect Structure of BaTiO3 Thin Films

MRS Proceedings ◽

10.1557/proc-310-409 ◽

1993 ◽

Vol 310 ◽

Cited By ~ 1

Author(s):

L.A. Wills ◽

B.W. Wessels

Keyword(s):

Thin Films ◽

Cross Section ◽

Defect Structure ◽

Oxygen Vacancies ◽

Vacuum Annealing ◽

Deep Level ◽

Energy Levels ◽

The Other ◽

Optical Cross Section ◽

Impurity Defects

AbstractThe defect structure of BaTiO3 thin films grown on (100) Si was examined using transient photocapacitance spectroscopy. The concentration, optical cross section and associated energy levels of both native and impurity defects in as-grown and annealed BaTiO3 films were evaluated. Deep level defects withpeak energies of Ev+1.8, Ev+2.4, Ev+2.7, Ev+3.0-3.1 and Ev+3.2-3.3 eV were observed in the as-grown films. Upon vacuum annealing, the concentration of the traps at Ev+3.0 and Ev+3.2 eV increased while the concentration of the traps at Ev+ 1.8 and Ev+2.4 eV decreased. The levels at Ev+3.0-3.1 and Ev+3.2-3.3 eV are attributed to oxygen vacancies. The other levels are tentatively ascribed to Fe and Fe related defects.

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Experimental and Theoretical Determinations of the5dPhotoionization Cross Section in Laser-Excited Barium Atoms between 15 and 150 eV Photon Energy

Physical Review Letters ◽

10.1103/physrevlett.57.306 ◽

1986 ◽

Vol 57 (3) ◽

pp. 306-309 ◽

Cited By ~ 28

Author(s):

J. M. Bizau ◽

D. Cubaynes ◽

P. Gerard ◽

F. J. Wuilleumier ◽

J. L. Picqué ◽

...

Keyword(s):

Cross Section ◽

Photon Energy

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Collective Effects on the Transition Bremsstrahlung Spectrum due to the Polarization Interaction in Nonideal Plasmas

Zeitschrift für Naturforschung A ◽

10.1515/zna-2009-1-208 ◽

2009 ◽

Vol 64 (1-2) ◽

pp. 49-53

Author(s):

Hwa-Min Kim ◽

Young-Dae Jung

Keyword(s):

Cross Section ◽

Impact Parameter ◽

Photon Energy ◽

Parameter Analysis ◽

Collective Effects ◽

Bremsstrahlung Spectrum ◽

Collective Effect ◽

Bremsstrahlung Radiation ◽

Polarization Interaction ◽

Nonideal Plasmas

The collective effects on the transition bremsstrahlung spectrum due to the polarization interaction between the electron and Debye shielding cloud of an ion are investigated in nonideal plasmas. The impact parameter analysis with the effective pseudopotential model taking into account the nonideal collective and plasma screening effects is applied to obtain the bremsstrahlung radiation cross-section as a function of the nonideality plasma parameter, Debye length, photon energy, and projectile energy. It is shown that the collective effects enhance the bremsstrahlung radiation cross-section and decrease with increasing impact parameter. It is also shown that the collective effect is the most significant near the maximum position of the bremsstrahlung cross-section. In addition, it is shown that the collective effect decreases with an increase of the radiation photon energy

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