Quantum transport in quasiperiodic lattice systems in the presence of Buttiker probes

Abstract

Quasiperiodic lattice systems offer diverse transport properties. In this paper, we investigate environment-induced effects on the transport properties for quasiperiodic systems, namely the one-dimensional Aubry-André-Harper (AAH) lattice chain and its generalized version (GAAH), by considering the Büttiker probe approach. We first consider a voltage-probe situation and study the electrical conductance properties in the linear-response regime. At zero temperature, we observe an enhancement in conductance for small probe coupling strength γ with a power-law scaling γ4 at all the no-transport regimes, located both inside and outside of the band of the original system. For large probe coupling strengths, the conductance at all Fermi energies is the same and decays as a power law with scaling 1/γ4. This particular scaling survives even in the finite-temperature limit. Interestingly, this scaling result is different from the one recently predicted following the local Lindblad master equation approach. The transport eventually becomes diffusive for all energy ranges and in all regimes of the original model for a sufficiently strong coupling with the probes. We further extend our study and consider voltage-temperature probes to analyze the thermoelectric performance of the chain in terms of the figure of merit. We also demonstrate the validity of two recently obtained bounds on thermoelectric efficiency which are tighter than the seminal Carnot bound, in the presence of voltage-temperature probes.