Ohmic Losses in Valence-band Photoemission Experiments

Robert Haslinger; Robert Joynt

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Ohmic Losses in Valence-band Photoemission Experiments

Robert Haslinger·Robert Joynt

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Abstract

Photoemission experiments involve the motion of an electron near a conducting surface. This necessarily generates heat by ohmic losses from eddy currents. This inelastic scattering of the electrons will result in a downward shift in observed spectra. This effect is most pronounced in poorly conducting metals: in good metals the electron's field is screened out of the material, while insulators are by definition unable to absorb electromagnetic energy at low frequencies. We give a classification of photoemission processes which shows that the effect is an extrinsic proces distinct from final state effects. The shift is illustrated by a model system with a Drude-like conductivity function and a temperature-dependent relaxation time. We give a brief experimental survey of systems in which the ohmic losses may be significant.

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Robert Haslinger, Robert Joynt. 2000-08-14. Ohmic Losses in Valence-band Photoemission Experiments. https://arxiv.org/abs/cond-mat/0008205

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