In frames of the one-instanton approximation the field and temperature dependence of the 2D - dissipative tunneling probability for the model double-oscillator potential in the conditions of an external electric field at a finite temperature with the influence of two local phonon modes for the quantum dots in the system of combined atomic force / scanning tunneling microscope, have been theoretically investigated. It is shown that in synchronous mode, the parallel transfer of tunneling particles from the cantilever tip to a quantum dot with account of the two local phonon modes influence leads to appearance of two stable peaks on the field dependence of the 2D - dissipative tunneling probability. A qualitative comparison of the theoretical curve in the limit of weak dissipation with the experimental tunneling current-voltage characteristics for growing quantum dots of colloidal gold under the cantilever tip at the initial stage of the quantum dot formation, when the size of quantum dots does not exceed 10 nm, has been fulfilled. It was found that on the temperature dependence of the 2D- dissipative tunneling probability one of two stable peaks, corresponding to interaction of the tunneling particle with two local phonon modes, can be splitted into two peaks, which is associated with mechanism of the tunneling channels interference. It has been found, that near the bifurcation point the theoretically predicted and experimentally observed a quantum-beat mode, can be realized.
73.90.+f Other topics in electronic structure and electrical properties of surfaces, interfaces, thin films, and low-dimensional structures
$^1$Department of theoretical physics, Faculty of Physics, Lomonosov Moscow State University. Moscow 119991, Russia.
$^2$Department of physics, Penza State University, Penza 440026, Russia.