Nonequilibrium crackling charge transfer in 2-D molecular layers

Critical dynamics of isomeric structural transitions in 2D organic self-assembled monolayer has been investigated in a hybrid organic-inorganic device consisting of a field effect transistor coupled through the self assembled 2D molecular layer to a system of nanocrystals acting as light sensitive gate for the transistor. Upon light illumination charge avalanches in the transistor's current noise time traces appear. Time evolution of avalanches has been associated with charge accumulation in the surface traps, which reduces the dipole moment of the molecules, decreases the intermolecular coupling, and as a consequence, reduces the critical disorder of the molecular system. The critical dynamics of the system can be thus tuned by light illumination.