We analyze a quantum version of the Monge–Kantorovich optimal transport problem. The cost related to Hermitian matrix C is minimized over set all bipartite coupling states $$\rho ^{AB}$$ with fixed reduced density matrices ^A$$ and ^B$$ size m n. minimum $$\textrm{T}^Q_{C}(\rho ^A,\rho ^B)$$ can be efficiently computed using semidefinite programming. In case $$m=n$$ $$\textrm{T}^Q_{C}$$ gives s...

This paper is about adiabatic transport in quantum pumps. The notion of “energy shift”, a self-adjoint operator dual to the Wigner time delay, plays a role in our approach: It determines the current, the dissipation, the noise and the entropy currents in quantum pumps. We discuss the geometric and topological content of adiabatic transport and show that the mechanism of Thouless and Niu for qua...

Self-assembled InAs nanostructures in InP, comprising quantum wells, quantum wires, and quantum dots, are studied in terms of their formation and properties. In particular, the structural, optical, and anisotropic transport properties of the nanostructures are investigated. The focus is a comprehending exploration of the anisotropic in-plane transport in large ensembles of laterally coupled InA...

Previous studies of quantum chaotic scattering established a connection between classical dynamics and quantum transport properties: Integrable or mixed classical dynamics can lead to sharp conductance fluctuations but chaos is capable of smoothing out the conductance variations. Relativistic quantum transport through single-layer graphene systems, for which the quasiparticles are massless Dira...

Quantum diffusion in a biased kicked Harper system, modeling field-induced transport in superlattices, is studied for fully chaotic dynamics of the underlying classical system. Under these conditions, the classical transport is diffusive whereas the quantum diffusion can be either enhanced or suppressed for commensurable or incommensurable ratio of the Bloch period to the driving period, respec...

Electrons in two dimensions and strong magnetic fields can form an insulating two-dimensional system with conducting one-dimensional channels along the edge. Electron interactions in these edges can lead to independent transport of charge and heat, even in opposite directions. Here, we heat the outer edge of such a quantum Hall system using a quantum point contact. By placing quantum dots upstr...

Within the Lindblad formalism we consider an interacting spin chain coupled locally to heat baths. We investigate the dependence of the energy transport on the type of interaction in the system as well as on the overall interaction strength. For a large class of couplings we find a normal heat conduction and confirm Fourier’s Law. In a fully quantum mechanical approach linear transport behavior...

We develop a quantum scattering model to describe the exciton transport through the FennaMatthews-Olson(FMO) complex. It is found that the exciton transport involved the optimal quantum coherence is more efficient than that involved classical behavior alone. Furthermore, we also find that the quantum resonance condition is easier to be fulfilled in multiple pathways than that in one pathway. We...