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We present calculated electron stopping powers (SPs) for 31 elemental solids (Li, Be, glassy C, graphite, diamond, Na, Mg, K, Sc, Ti, V, Fe, Y, Zr, Nb, Mo, Ru, Rh, In, Sn, Cs, Gd, Tb, Dy, Hf, Ta, W, Re, Os, Ir, and Bi). These SPs were determined with an algorithm previously used for the calculation of electron inelastic mean free paths and from energy-loss functions (ELFs) derived from experimental optical data. The SP calculations were made for electron energies between 100 eV and 30 keV and supplement our earlier SP calculations for ten additional solids (Al, Si, Cr, Ni, Cu, Ge, Pd, Ag, Pt, and Au). Plots of SP versus atomic number for the group of 41 solids show clear trends. Multiple peaks and shoulders are seen that result from the contributions of valence-electron and various inner-shell excitations. Satisfactory agreement was found between the calculated SPs and values from the relativistic Bethe SP equation with recommended values of the mean excitation energy (MEE) for energies above 10 keV. We determined effective MEEs versus maximum excitation energy from the ELFs for each solid. Plots of effective MEE versus atomic number showed the relative contributions of valence-electron and different core-electron excitations to the MEE. For a maximum excitation energy of 30 keV, our effective MEEs agreed well for Be, graphite, Na, Al, and Si with recommended MEEs; a difference for Li was attributed to sample oxidation in the SP measurements for the recommended MEE. Substantially different effective MEEs were found for the three carbon allotropes (graphite, diamond, and glassy C). [ABSTRACT FROM AUTHOR]

We calculated electron inelastic mean free paths (IMFPs) for liquid water from its optical energy-loss function (ELF) for electron energies from 50 eV to 30 keV. These calculations were made with the relativistic full Penn algorithm that has been used for previous IMFP and electron stopping-power calculations for many elemental solids. We also calculated IMFPs of water with three additional algorithms: the relativistic single-pole approximation, the relativistic simplified single-pole approximation, and the relativistic extended Mermin method. These calculations were made by using the same optical ELF in order to assess any differences of the IMFPs arising from choice of the algorithm. We found good agreement among the IMFPs from the four algorithms for energies over 300 eV. For energies less than 100 eV, however, large differences became apparent. IMFPs from the relativistic TPP-2M equation for predicting IMFPs were in good agreement with IMFPs from the four algorithms for energies between 300 eV and 30 keV, but there was poorer agreement for lower energies. We calculated values of the static structure factor as a function of momentum transfer from the full Penn algorithm. The resulting values were in good agreement with results from first-principle calculations and with inelastic X-ray scattering spectroscopy experiments. We made comparisons of our IMFPs with earlier calculations from authors who had used different algorithms and different ELF data sets. IMFP differences could then be analyzed in terms of the algorithms and the data sets. Finally, we compared our IMFPs with measurements of IMFPs and of a related quantity, the effective attenuation length. There were large variations in the measured IMFPs and effective attenuation lengths (as well as their dependence on electron energy). Further measurements are therefore required to establish consistent data sets and for more detailed comparisons with calculated IMFPs. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Presents a study that discussed the theoretical basis for understanding photo-assisted resonant tunneling. Effects of a photon field on an energy state; Information on the behavior of resonant tunneling heterojunctions; Use of double-barrier quantum wells.

Presents an abstract of the article 'The Role of Inelastic Exchange Scattering in Spin Polarization Experiments,' by D.R.Penn, S.P. Apell and S.M. Girvin.