Activation Mechanism of the Cyclic Switchover Effect for Quantum Selective Detection with Dendritic Yanson Point Contacts

Development of quantum selective sensors requires a detailed study of nature, kinetic parameters, and activation mechanisms of all phases of the cyclic switchover effect. Yanson point contact is the main tool to solve emerging tasks. When placed in an ion-conducting medium, it can function as an electrochemical gapless electrode system (GES). The transformations in the Yanson point-contact nanostructure are shaped by the quantum shell effect and the GES processes. We show that a GES in an electric field is as a system with a positive feedback which determines the dynamics of the point-contact resistance variation in an ion-conducting medium. Analysis of the experimental data on the dynamics of electric conductance and lifetime of dendritic Yanson point contacts during the cyclic switchover effect allows one to study the peculiarities of the processes that can enable the realization of the quantum mechanism of selective detection and lead to an enhanced sensitivity of point-contact sensors to liquid and gaseous analytes. A mathematical model for the anode destruction of dendritic copper point contacts during the cyclic switchover process is proposed and discussed.