Kinetics of Polaron Capture by Traps in a Lithium Niobate Crystal

The problem of a reversible transformation and trapping of small-radius polarons in a lithium niobate (LN) crystal is considered within the framework of the integral encounter theory, which is binary in the concentration of reactants. Analytical solutions are obtained for the relaxation kinetics of polarons, their lifetimes, and the rate constants of the corresponding channels of a multistage reaction controlled by polaron mobility. The temperature and concentration dependencies of the observed quantities are analyzed. It is shown that at low temperatures polarons accumulate in a bound state characterized by an anomalously low relaxation rate.