The combination of internal photoemission and near-field optics is proposed as a generally applicable approach to study the lateral variations of solid interface properties such as energy barriers and electron-hole recombination rates. A successful test on Pt–GaP is described in which topographic and nontopographic phenomena are revealed, in particular recombination rate variations and small lateral changes of the Schottky barrier height.

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CsI photocathodes were studied in order to evaluate their potential use as large photo converters in RICH detectors for the PID system of ALICE at LHC in heavy-ion collider mode. It has been demonstrated that a quantum efficiency close to the reference value obtained on small samples can be obtained on CsI layers evaporated on large pad electrodes operated in a MWPC at atmospheric pressure. We present a survey of the results obtained in the laboratory on small samples irradiated with UV-monochromatic beams and with large area RICH detectors of proximity-focusing geometry in a 3 GeV/c pion beam.

Internal photoemission phototransport measurements revealed 0.27±0.04 eV conduction- and valence-band discontinuities induced by a Si intralayer at p-GaAs(100)/n-GaAs(100) homojunctions. The interface dipole originating from the heterovalent character of the Si—GaAs bonds raises the bands of the GaAs overlayer above that of the GaAs substrate.