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arXiv · 2304.00203

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

M. E. Raikh
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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}.

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M. E. Raikh. 2023-04-01. Effect of the resonant ac-drive on the spin-dependent recombination of polaron pairs: Relation to organic magnetoresistance. https://doi.org/10.1016/j.ssc.2023.115213

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