RESONANCE IN SCANNING TUNNELING SPECTROSCOPY

The spectra recorded in experiments with a scanning tunnelling microsc ope (STM) are analyzed based on the data borrowed from the literature and our own results. Theoretical interpretation of these spectra is pr oposed. It is shown that elastic 3D-scattering of electrons from the s urface of a scanned sample is responsible for fast decay of resonances in the low-field spectrum part and drastic upsurge of resonances at v oltages V > b(2)/2 (b is the vector of a reciprocal lattice of surface atoms), which in metals amounts to 15-30 V. It turned out that inelas tic scattering of electrons from individual adatoms conduces to broade ning of resonance peaks in the low-field part of the spectrum and endo ws their slopes with a small-scale (fine) oscillatory structure. A new procedure for observing vibrational transitions in adsorbed particles with an STM is proposed (''intracavity electron spectroscopy''). The efficiency of the relay mechanism of electron emission by tunnelling n ano-size contacts is assessed.