Inelastic interactions

Powell C J 1994 Inelastic interactions of electrons with surfaces applications to Auger-electron spectroscopy and x-ray photoelectron spectroscopy Surf. Sc/. 299-300 34... 

The phenomena of beam broadening as a function of specimen thickness are illustrated in Fig. 4.20 each figure represents 200 electron trajectories in silicon calculated by Monte Carlo simulations [4.91, 4.95-4.97] for 100-keV primary energy, where an infinitesimally small electron probe is assumed to enter the surface. In massive Si the electrons suffer a large number of elastic and inelastic interactions during their paths through the material, until they are finally completely stopped. The resulting penetration depth of the electrons is approximately 50 pm and in the... 

Tamayo, J. and Garcia, R., Effects of elastic and inelastic interactions on phase contrast images in tapping-mode scanning force microscopy. Appl. Phys. Lett., 71(16), 2394-2396 (1997). 

Right Fig. 3. Elastic and inelastic interactions between incident electrons and atom. 

The interactions to which the measuring samples are exposed can be of elastic or inelastic type (in the physical sense). Figure 2.11 shows schematically the difference between elastic and inelastic interactions. 

The majority of analytical methods are based on inelastic interactions. In contrast to elastic interactions, in case of inelastic interactions both the energy of the measuring system, Ein, and the intrinsic energy of the constituents of the measuring sample, E0, will be changed in such a way that the following condition is fulfilled ... 

Electron beams Particle-matter interactions > (a) Inelastic interactions (energy transfer with sample species) SPECTROSCOPY (b) Elastic interactions (energy transfer) DIFFRACTION, MICROSCOPY... 

Landauer proposed in 1957 the first mesoscopic theoretical approach to charge transport [176]. Transport is treated as a scattering problem, ignoring initially all inelastic interactions. Phase coherence is assumed to be preserved within the entire conductor. Transport properties, such as the electrical conductance, are intimately related to the transmission probability for an electron to cross the system. Landauer considered the current as a consequence of the injection of electrons at one end of a sample, and the probability of the electrons reaching the other end. The total conductance is determined by the sum of all current-carrying eigenmodes and their transmission probability, which leads to the Landauer formula of a ID system ... 

The organization of this chapter is as follows. In the following section, Sec. 4.2, the elastic and inelastic interaction cross sections necessary for simulating track structure (geometry) will be discussed. In the next section, ionization and excitation phenomena and some related processes will be taken up. The concept of track structure, from historical idea to modern track simulation methods, will be considered in Sec. 4.4, and Sec. 4.5 deals with nonhomogeneous kinetics and its application to radiation chemistry. The next section (Sec. 4.7) describes some application to high temperature nuclear reactors, followed by special applications in low permittivity systems in Sec. 4.8. This chapter ends with a personal perspective. For reasons of convenience and interconnection, it is recommended that appropriate sections of this chapter be read along with Chapters 1 (Mozumder and Hatano), 2 (Mozumder), 3 (Toburen), 9 (Bass and Sanche), 12 (Buxton), 14 (LaVerne), 17 (Nikjoo), and 23 (Katsumura). 

Physically, the Brillouin spectrum arises from the inelastic interaction between a photon and the hydrodynamics modes of the fluid. The doublets can be regarded as the Stokes and anti-Stokes translational Raman spectrum of the liquid. These lines arise due to the inelastic collision between the photon and the fluid, in which the photon gains or loses energy to the phonons (the propagating sound modes in the fluid) and thus suffer a frequency shift. The width of the band gives the lifetime ( 2r)-1 of a classical phonon of wavenumber q. The Rayleigh band, on the other hand, represents the... 

Because all phases of the interaction of the incident energetic ion beam with materials, including kinematics and cross section of the elastic collision and the energy losses by means of inelastic interaction with the electrons are readily calculable, the analysis lends itself to computer simluation. One of the first such programs, developed at IBM (4), is used at NRL, while other programs have also been developed at a number of other laboratories. 

Equations (3.21)—(3.22) satisfy the conservation law for elastic matter-radiation interactions, )rK(ct )j2 -1- tK(ct>) 2 = 1, and the very useful relation tK(co) = 1 + rK(o>), which accounts for the symmetry of the matter system (when the dipoles lie in the 2D layer) and which is valid for elastic and inelastic interactions. They are obtained if the expression for RK(to) has only a pure imaginary part, the real part being included in the eigenenergy ha>0. 

This is a surface vibrational spectroscopic technique that involves the irradiation of the adsorbate-metal interface with a beam of low-energy (2 to 10 eV) electrons and the measurement of the energies of the backscattered electrons energy losses below 0.5 eV are due mainly to inelastic interactions with metal-surface phonons and adsorbate vibrational excitations. The extremely high sensitivity of HREELS makes possible measurements of adsor-... 

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