Multiverse-weighted kinetic Monte Carlo and its application to modeling of optoelectronic processes in organic light-emitting diodes

Kinetic Monte Carlo (KMC) can be used to simulate the behavior of a quantum system governed by incoherent transitions between its states. At each KMC step, the system evolves by executing a transition that is randomly chosen according to its rate, and a contribution to the average of a system observable is calculated. In traditional KMC, only the contribution of the transition that is actually chosen is accounted for when calculating system observables. We propose here an extension of KMC, which we call multiverse-weighted kinetic Monte Carlo (MKMC). In MKMC, also the contributions of all other transitions, that are not chosen but could have been chosen, are taken into account, weighted according to their rates. Because in MKMC the average of an observable is based on more information than in traditional KMC, one may expect that the observable can be calculated with higher accuracy. As a demonstration we apply MKMC to the simulation of several optoelectronic processes in organic light-emitting diodes. We demonstrate situations where the accuracy of a system observable calculated with MKMC is indeed much better than with traditional KMC and also identify situations where this is not the case.