Recently, we introduced a comprehensive theory of carrier recombination and energy transport at organic and hybrid organic/inorganic semiconductor heterojunctions (OI-HJ).[1] The OI-HJ has been found to play an important role in numerous devices in photodetection and energy power conversion. By developing a quantum mechanical model of the hybrid charge transfer exciton (HCTE) that is the intermediate between exciton generation and charge collection, we have been successful in understanding the behavior of several organic/III-V semiconductor OI-HJs.[2] More recently, we have extended this analysis to quantify the behavior of a new class of OI-HJs: those comprising a very thin film organic layered on a 2D transition metal dichalcogenide monolayer. For this latter purpose, we have fabricated an organic/WS2 OI-HJ photodetector used to elaborate the charge and energy transport across these limited dimensional systems.[3] In this talk, we will discuss the theoretical framework of HCTE dynamics, along with measurement of its properties and its application to photodetection and other optoelectronic systems consisting of combinations of excitonic and conventional semiconductors.

[1] C. K. Renshaw and S. R. Forrest, "Excited State and Charge Dynamics of Hybrid Organic/Inorganic Heterojunctions. I. Theory," Phys. Rev. B, vol. 90, p. 045302, 2014.
[2] A. Panda, K. Ding, and S. R. Forrest, "Free and trapped charge transfer excitons at a ZnO/small molecule heterojunction," Phys. Rev. B, vol. 94, p. 125429, 2016.
[3] X. Liu, J. Gu, K. Ding, D. Fan, X. Hu, Y.-W. Tseng, et al., "Photoresponse of an Organic Semiconductor/Two-Dimensional Transition Metal Dichalcogenide Heterojunction," Nano Lett., vol. 17, p. 3176, 2017.