Electron counting statistics of open quantum systems

Abstract

Electron transport through organic molecules is a process fundamental to life and plays a central role in the emerging field of molecular electronics. This thesis presents an investigation of electron transport through molecular systems from the perspective of full counting statistics. An extension of a Markovian counting statistics framework to a non-perturbative setting is presented which allows for an exact treatment of the phonon bath. This framework is applied to a theoretical photocell device inspired by the photosystem II reaction centre. It is demonstrated that the asymmetric coupling of excitation and charge transfer states to a structured spectral density rather than a smooth low energy background has the effect of reducing the output current along with an associated reduction in the current fluctuations. The insights gained from this are discussed in terms of design principles for pigmentprotein complexes used in nano-electronic devices and their relevance for biological function in vivo. Finally, the asymmetric coupling of excitation and charge transfer states to their vibrational environment is investigated more closely through the dynamics of a dimer model and the effect of the output current statistics of a prototype photocell

    Similar works