Combined impact of entropy and carrier delocalization on charge transfer exciton dissociation at the donor-acceptor interface

摘要

Several models of the charge transfer exciton (CTE) have been proposed toexplain its dissociation at the donor-acceptor (DA) interface. However, theunderlying physics is still under debate. Here, we derive temperature($T$)-dependent tight-binding model for an electron-hole pair at the DAinterface. The main finding is the existence of the localization-delocalizationtransition at a critical $T$, which can explain the CTE dissociation. Thepresent study highlights the combined effect of entropy (finite-$T$) andcarrier delocalization in the CTE dissociation.