Estimation of Exciton Diffusion Lengths of Organic Semiconductors in Random Domains


Jingrun Chen, Soochow University


2019.06.27 14:00-15:00


Room 306, No. 5 Science Building


Exciton diffusion length plays a vital role in the function of opto-electronic devices. Oftentimes, the domain occupied by a organic semiconductor is subject to surface measurement error. In many experiments, photoluminescence over the domain is measured and used as the observation data to estimate this length parameter in an inverse manner based on the least square method. However, the result is sometimes found to be sensitive to the surface geometry of the domain. We propose an asymptotic-based method as an approximate forward solver whose accuracy is justified both theoretically and numerically. It only requires to solve several deterministic problems over a fixed domain. Therefore, for the same accuracy requirement we tested here, the running time of our approach is more than one order of magnitude smaller than that of directly solving the original stochastic boundary-value problem by the stochastic collocation method. In addition, from numerical results we find that the correlation length of randomness is important to determine whether a 1D reduced model is a good surrogate. This is joint work with Ling Lin (Sun Yat-sen University), Zhiwen Zhang (University of Hong Kong), and Xiang Zhou (City University of Hong Kong).