GEOMETRICAL RESONANCE EFFECTS IN HTSC BREAK JUNCTIONS

A periodic structure has been observed in the tunneling characteristic s of HTSC break junctions. This structure is explained in terms of the electron-hole interference effect in the surface layer, which causes the formation of bound states in the normal regions N of the SNINS-typ e junctions. Good qualitative agreement has been found between experim ental data and the predictions of the Arnolds proximity model. Several parameters of the SNINS-type structures have been derived from studie s of Fiske resonances in HTSC Josephson break junctions in weak magnet ic fields.