Matrix element and transition rate for Auger neutralization of low energy ions near metal surfaces

Hentschke, Reinhard; Snowdon, K.J.; Hertel, P.; Heiland, W.

doi:10.1016/0039-6028(86)90210-4

Cited by 64 publications

(11 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although the influence of the crystal structure on the ion fractions of slow ions scattered from metals have been known for a long time [129,130,131,132,133], rather simple and general models [76,77,134] cannot explain the details of the experimental results. Therefore, a more realistic description of the metal surface is needed to account for observed crystal effects in the Auger rate.…”

Section: Corrugated Surfacementioning

confidence: 75%

See 1 more Smart Citation

Auger neutralization and ionization processes for charge exchange between slow noble gas atoms and solid surfaces

Monreal

2014

Progress in Surface Science

View full text Add to dashboard Cite

Electron and energy transfer processes between an atom or molecule and a surface are extremely important for many applications in physics and chemistry. Therefore a profound understanding of these processes is essential in order to analyze a large variety of physical systems. The microscopic description of the two-electron Auger processes, leading to neutralization/ionization of an ion/neutral atom in front of a solid surface, has been a long-standing problem. It can be dated back to the 1950s when H. D. Hagstrum proposed to use the information contained in the spectrum of the electrons emitted during the neutralization of slow noble gas ions as a surface analytical tool complementing photoelectron spectroscopy. However, only recently a comprehensive description of the Auger neutralization mechanism has been achieved by the combined efforts of theoretical and experimental methods. In this article we review the theoretical models for this problem, stressing how their outcome compare with experimental results. We also analyze the inverse problem of Auger ionization. We emphasize the understanding of the key quantities governing the processes and outline the challenges remaining. This opens new perspectives for future developments of theoretical and experimental work in this field.

show abstract

Section: Corrugated Surfacementioning

confidence: 75%

“…Snowdon et al [76,77] performed one of the first "modern" calculations of the Auger neutralization rate. They used a free-electron model for the metal in which the electron wave functions were that of a simple step-potential surface.…”

Section: Theoretical Modelsmentioning

confidence: 99%

Auger neutralization and ionization processes for charge exchange between slow noble gas atoms and solid surfaces

Monreal

2014

Progress in Surface Science

View full text Add to dashboard Cite

show abstract

“…These are complex quantum-mechanical scattering calculations, where many approximations are required. Horiguchi et al 27 and Hentschke et al 28 computed Auger rates for a proton-metal system using analytical wave functions for the metal electrons ͑those of a step potential͒. They simplified the eight dimensional k-space integration by taking the contribution of electrons at the Fermi level normal to the surface.…”

Section: Overviewmentioning

confidence: 99%

“…5 In an analogous way, the theoretical work can also be divided into calculations concerning electron emission, [21][22][23][24][25][26] or neutralization rates. [27][28][29][30][31][32][33][34][35] Propst 21 calculated the Auger matrix elements using a WKB approach for the wave function of the captured electron tunneling through the ionsurface barrier. His work qualitatively reproduces the experimental spectra by Hagstrum.…”

Section: Overviewmentioning

confidence: 99%

Theory of Auger neutralization and deexcitation of slow ions at metal surfaces

et al. 1998

View full text Add to dashboard Cite

The contribution of conduction electrons to the Auger neutralization rate of a slow ion at a metal surface has been calculated. We have considered the scattering of He ϩ on Al and studied the effect of the ion potential on the neutralization rate. This has been accomplished by taking into account the modification of the wave function of the captured electron induced by the presence of the ion. The effect of the ion potential is shown to increase the Auger neutralization rate. We have also calculated the Auger deexcitation of He* (nϭ2) atoms in front of an aluminum surface, including the distorsion created by the surface on the atom states. In this case, the deexcitation rate is reduced by the mixing of atom and surface states, which also leads to a nonvanishing deexcitation rate of metastable He (2 1 S). ͓S0163-1829͑98͒06543-6͔

show abstract

“…(5) and interchanging the order of the integrations over r and q, we can integrate out the plane-wave factors in the coordinates x and y and use the resulting Dirac 5 functions 5(q"-k"+v") and 5(q -k~+ v ) to perform the q"and q" integrations. As an intermediate step in the evaluation of the matrix element (5), we then obtaiñ J(k;u, i,~;v, D)=(2m')' f dq, FJ(q, )exp( iDq, ) fdz[g"'(z)]'exp[i(q, +u, )z], (25) where the function F (q, ) is defined by FJ(q, } = f (k"', ky', q, }, and (26) k"' = k"u", k ' = k"v (27) and 0 I -(q, )= f dz exp[i(q, -p+ -)z] (28) are the x and y components, respectively, of the momentum of the metal electron relative to the moving ion. exp(ik, z ) in gk ' (z) and from the refiected wave 2 exp(ik, z ), respectively.…”

Section: B Jellium Wave Functionsmentioning

confidence: 99%

One-electron matrix elements in the theory of ion–metal-surface scattering

Wille

1992

Phys. Rev. A

View full text Add to dashboard Cite

A systematic evaluation of one-electron matrix elements appearing in the theory of charge-exchange processes in ionmetal-surface scattering is presented. The conduction-band electrons are described by jellium-type wave functions, while hydrogenic wave functions are employed for the electronic states of the ion. By applying Fourier-transform methods and complex integration techniques, exact closed-form expressions for overlap and Coulomb matrix elements are derived for arbitrary hydrogenic quantum numbers, momenta of the conduction-band electrons, and distances of the ion from the surface. The general case of arbitrary energy difference between initial and final state {including the strictly resonant case) is treated. For the near-resonant case, an expansion of the matrix elements about the resonant limit is derived. The effect of the motion of the ion is taken into account by including electronic translational factors. The actual computation of the matrix elements involves multiple summations, which can be accurately performed even for high-lying ionic Rydberg states. Structural properties of the matrix elements are revealed by studying, for typical cases, their dependence on the various parameters. Possible applications of our method are indicated.PACS number(s): 79.20. Rf, 79.80.+w

show abstract

Matrix element and transition rate for Auger neutralization of low energy ions near metal surfaces

Cited by 64 publications

References 18 publications

Auger neutralization and ionization processes for charge exchange between slow noble gas atoms and solid surfaces

Auger neutralization and ionization processes for charge exchange between slow noble gas atoms and solid surfaces

Theory of Auger neutralization and deexcitation of slow ions at metal surfaces

One-electron matrix elements in the theory of ion–metal-surface scattering

Contact Info

Product

Resources

About