Coherent destruction of the current through molecular wires using short laser pulses

TL;DR

This paper investigates how short laser pulses can suppress electron transport in molecular wires, demonstrating control over current flow even with single-site wires and including electron interactions.

Contribution

It introduces a method to control molecular wire currents using Gaussian laser pulses, extending the phenomenon of coherent destruction of tunneling to more complex, interacting systems.

Findings

Laser pulses can suppress current in single-site molecular wires.

Electron correlations do not negate the current suppression.

Destructive quantum effects occur under specific electric field conditions.

Abstract

A molecular wire coupled to two electron reservoirs is investigated within a tight-binding approach including spin and Coulomb interaction. Under the assumption of weak coupling to the electron reservoirs a quantum master equation can be derived for the electron transport through the wire. Motivated by the phenomenon of coherent destruction of tunneling for monochromatic laser fields, the influence of Gaussian laser pulses on the transport through the wires is studied. For situations in which the maximum amplitude of the electric field fulfills the conditions for the destructive quantum effect the average current through the system can be suppressed even for a wire consisting of only one site. Turning on the electron correlation does not destroy the suppression of the current by the laser.