Bistable molecular conductors with a field-switchable dipole group

TL;DR

This paper proposes bistable stator-rotor molecules with a field-switchable dipole, enabling reversible control of their conduction state for potential use in molecular electronics.

Contribution

It introduces a new class of bistable molecules with a switchable dipole, demonstrating their potential for electronic device applications.

Findings

The dipole orientation can be switched by an external electric field.

The two states exhibit opposite current-voltage characteristics.

Potential for integration into molecular electronic components.

Abstract

A class of bistable "stator-rotor" molecules is proposed, where a stationary bridge (stator) connects the two electrodes and facilitates electron transport between them. The rotor part, which has a large dipole moment, is attached to an atom of the stator via a single sigma bond. Hydrogen bonds formed between the rotor and stator make the symmetric orientation of the dipole unstable. The rotor has two potential minima with equal energy for rotation about the sigma bond. The dipole orientation, which determines the conduction state of the molecule, can be switched by an external electric field that changes the relative energy of the two potential minima. Both orientation of the rotor correspond to asymmetric current-voltage characteristics that are the reverse of each other, so they are distinguishable electrically. Such bistable stator-rotor molecules could potentially be used as parts of molecular electronic devices.