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Surface plasmons propagating parallel to the grooves of a large amplitude grating
A64 240
Surface Science 114 (1982) 240-250 North-Holland Publishing Company
S U R F A C E P L A S M O N S P R O P A G A T I N G PARALLEL TO T H E G R O O V E S OF A LARGE A M P L I T U D E GRATING * N.E. GLASS
Department of Physics, University of California, lrvine, California 92717, USA and A.A. MARADUDIN
**
Max-Planck,lnstitut fi~r Festki~rperforschung, Heisenbergstrasse 1, D-7000 Stuttgart 80, Federal Republic of Germany Received 30 June 1981 The dispersion relation is obtained for a surface plasmon propagating parallel to the grooves of a large amplitude grating. Two variants of the Rayleigh method are used: the first requires the evaluation of the zeros of a determinant; the second yields the dispersion relation in terms of the solution of a matrix eigenvalue problem. The dispersion relations are solved numerically for a sinusoidal and for a symmetric sawtooth grating profile, yielding in each case an infinity of discrete branches.
Surface Science 114 (1982) 251-271 North-Holland Publishing Company
251
C O M P U T E R S I M U L A T I O N S OF L O W - E N E R G Y SCATI'ERING H.F. HELBIG
FROM
NICKEL
NEON-ION
CRYSTAI.,S
and M.W. LINDER
Clarkson College of Technology, Potsdam, New York 13676, USA and G.A. MORRIS
and S.A. STEWARD
Lawrence Livermore National Laboratory, Livermore, California 94550, USA Received 2 June 1981 ; accepted for publication 4 September 1981 The model of successive single binary elastic collisions used by a computer code called ARGUS is sufficiently accurate to reproduce the salient features of energy spectra that result from ion-surface scattering for the neon on nickel system down to incidence energies of 600 eV. Agreement with experimental measurements is at least as good as that obtained by more detailed calculations, which include the interactions of many particles. Many features of the backscattered energy spectra can be associated with a single, or at most a few, specific collision sequences. A R G U S selects sampling areas that are orthogonal to the incident beam direction rather than parallel to the surface. These sahapling areas are constructed from polygons formed by the intersection of the Wigner-Seitz cell of an atom with a plane perpendicular to the ion beam direction and passing through the center of the atom. These polygons of surface atoms form an overlapping mosaic. The irreducible portion of this mosaic (a type of primitive cell) that is visible along the ion beam direction is the required sampling area. This approach provides the m o s t economical sampling of the surface.
Surface Science 114 (1982) 240-250 North-Holland Publishing Company
S U R F A C E P L A S M O N S P R O P A G A T I N G PARALLEL TO T H E G R O O V E S OF A LARGE A M P L I T U D E GRATING * N.E. GLASS
Department of Physics, University of California, lrvine, California 92717, USA and A.A. MARADUDIN
**
Max-Planck,lnstitut fi~r Festki~rperforschung, Heisenbergstrasse 1, D-7000 Stuttgart 80, Federal Republic of Germany Received 30 June 1981 The dispersion relation is obtained for a surface plasmon propagating parallel to the grooves of a large amplitude grating. Two variants of the Rayleigh method are used: the first requires the evaluation of the zeros of a determinant; the second yields the dispersion relation in terms of the solution of a matrix eigenvalue problem. The dispersion relations are solved numerically for a sinusoidal and for a symmetric sawtooth grating profile, yielding in each case an infinity of discrete branches.
Surface Science 114 (1982) 251-271 North-Holland Publishing Company
251
C O M P U T E R S I M U L A T I O N S OF L O W - E N E R G Y SCATI'ERING H.F. HELBIG
FROM
NICKEL
NEON-ION
CRYSTAI.,S
and M.W. LINDER
Clarkson College of Technology, Potsdam, New York 13676, USA and G.A. MORRIS
and S.A. STEWARD
Lawrence Livermore National Laboratory, Livermore, California 94550, USA Received 2 June 1981 ; accepted for publication 4 September 1981 The model of successive single binary elastic collisions used by a computer code called ARGUS is sufficiently accurate to reproduce the salient features of energy spectra that result from ion-surface scattering for the neon on nickel system down to incidence energies of 600 eV. Agreement with experimental measurements is at least as good as that obtained by more detailed calculations, which include the interactions of many particles. Many features of the backscattered energy spectra can be associated with a single, or at most a few, specific collision sequences. A R G U S selects sampling areas that are orthogonal to the incident beam direction rather than parallel to the surface. These sahapling areas are constructed from polygons formed by the intersection of the Wigner-Seitz cell of an atom with a plane perpendicular to the ion beam direction and passing through the center of the atom. These polygons of surface atoms form an overlapping mosaic. The irreducible portion of this mosaic (a type of primitive cell) that is visible along the ion beam direction is the required sampling area. This approach provides the m o s t economical sampling of the surface.