Effect of the resonant ac-drive on the spin-dependent recombination of polaron pairs: Relation to organic magnetoresistance

Abstract

The origin of magnetoresistance is bipolar organic materials is the influence of magnetic field on the dynamics of recombination within localized electron-hole pairs. Recombination from the $S$ spin-state of the pair in preceded by the beatings between the states $S$ and $T_0$. Period of the beating is set by the the random hyperfine field. For the case when recombination time from $S$ is shorter than the period, we demonstrate that a {\em weak} resonant ac drive, which couples $T_0$ to $T_{+}$ and $T_{-}$ affects dramatically the recombination dynamics and, thus, the current A distinctive characteristics of the effect is that the current versus the drive amplitude exhibits a {\em maximum}.

5 Pages, 2 figures

References in corpus (4)

• Full counting statistics of strongly non-Ohmic transport through single molecules
• Numerical study of spin-dependent transition rates within pairs of dipolar and strongly exchange coupled spins with (s=1/2) during magnetic resonant excitation
• Analytical description of spin-Rabi oscillation controlled electronic transitions rates between weakly coupled pairs of paramagnetic states with S=1/2
• Comparative analysis of magnetic resonance in the polaron pair recombination and the triplet exciton-polaron quenching models