What is it about?
Electronic transport through a molecular tunnel junction composed of two polyyne-type carbynes separated by distance (4 Å ≥ dn ≥ 2.1 Å) based on Density Functional Theory/Non-Equilibrium Green’s Function (DFT/NEGF). The frontier molecular orbitals and bond lengths of the polyyne (dC–C ≈ 1.36 Å, dC≡C ≈ 1.26 Å) at 0.0 V become equal to those in cumulene-type carbynes (dC=C ≈ 1.28 Å) at 0.9 V occurring a semiconductor–metal transition for dn < 4 Å. I–V (dI/dV–V) curve presents switching behaviour up to 0.6 V and after a diode behaviour favoured as dn decreases, that is, to 4.0 Å is 3.3 nA (5 nS) while for 2.1 Å is 3750 nA (1500 nS) showing metallic nature. The log(I)–V [log(dI/dV)–V] curve exhibits the behaviour for low bias voltage while the I–dn curve is exhibited for high bias voltage.
Featured Image
Photo by Terry Vlisidis on Unsplash
Why is it important?
Carbynes have gained highlight due to their unique properties and applications in molecular electronics exhibiting resonant tunnel effect. So, we investigated tunneling at molecular junctions plays a role in the electronic transport of 1-D systems.
Perspectives
The exponential expression for G(d) fits perfectly with the Gmax result obtained with DFT/NEGF calculations. Transition Voltage Spectroscopy (TVS) confirms rectangular barrier and direct tunneling for Vd–s < ϕB/e playing a tunneling rule for electronic transport of these 1-D systems. So, investigate the electronic transport via tunneling in other 1D molecuar systems becomes trivial.
Prof. Dr. Carlos Alberto Brito da Silva Jr.
Universidade Federal do Para
Read the Original
This page is a summary of: Tunneling rules for electronic transport in 1-D systems, Molecular Physics, September 2021, Taylor & Francis,
DOI: 10.1080/00268976.2021.1976427.
You can read the full text:
Resources
Contributors
The following have contributed to this page
