Impact of dimerization and stretching on the transport properties of molybdenum atomic wires

TL;DR

This study investigates how dimerization and stretching affect the electronic transport properties of molybdenum atomic wires, revealing insulating behavior in dimerized structures and ferromagnetism in stretched chains.

Contribution

It provides a comprehensive analysis of the impact of structural variations on Mo wire conductivity and magnetic properties, combining electronic structure and transport simulations.

Findings

Dimerized Mo wires are insulating due to electronic gaps.

Transport properties vary from ohmic to tunneling with dimer number.

Stretched chains exhibit ferromagnetism.

Abstract

We study the electrical and transport properties of monoatomic Mo wires with different structural characteristics. We consider first periodic wires with inter-atomic distances ranging between the dimerized wire to that formed by equidistant atoms. We find that the dimerized case has a gap in the electronic structure which makes it insulating, as opposed to the equidistant or near-equidistant cases which are metallic. We also simulate two conducting one-dimensional Mo electrodes separated by a scattering region which contains a number of dimers between 1 and 6. The $I-V$ characteristics strongly depend on the number of dimers and vary from ohmic to tunneling, with the presence of different gaps. We also find that stretched chains are ferromagnetic.