Modeling the quantum to classical crossover in topologically disordered networks (Q2893129)

The transport in topologically disordered networks is modeled, where the networks are subjected to an environment that induces classical diffusion. The dynamics is phenomenologically described within the framework of the recently introduced quantum stochastic walk [\textit{J. D. Whitfield, C. A. Rodríguez-Rosario} and \textit{A. Aspuru-Guzik}, ``Quantum stochastic walks: a generalization of classical random walks and quantum walks'', Phys. Rev. A 81, No. 2, 022323 (2010; \url{doi:10.1103/PhysRevA.81.022323})], allowing the study of the crossover between coherent transport and purely classical diffusion. Applications are performed to systems that exhibit topological disorder and long-range dipole-dipole interactions. To study the transport efficiency, the authors connect the system with a source and a drain and provide a detailed analysis of their effects. It is found that the coupling to the environment removes all effects of localization and quickly lead to classical transport. Furthermore, on the level of the transport efficiency (i.e., calculating the expected survival time of the walker), it is obtained that the system can be well described by reducing it to a two-node network (a dimer).