Enhanced rectifying performance by asymmetrical gate voltage for BDC20 molecular devices

Abstract

By applying the asymmetrical gate voltage on the 1,4-bis (fullero[c]pyrrolidin-1-yl) benzene BDC 20 molecule, we investigate theoretically its electronic transport properties using the density functional theory and nonequilibrium Green's function formalism for a unimolecule device with metal electrodes.Interestingly, the rectifying characteristic with very high rectification ratio, 91.7 and 24.0, can be obtained when the gate voltage is asymmetrically applied on the BDC 20 molecular device. The rectification direction can be tuned by the different gate voltage applying regions. The rectification behavior is understood in terms of the evolution of the transmission spectrum and projected density of states spectrum with applied bias combined with molecular projected self-consistent Hamiltonian states analyses. Our finding implies that to realize and greatly promote rectifying performance of the BDC 20 molecule the variable gate voltage applying position might be a key issue.

Effect of gold electrode crystallographic orientations on charge transport through aromatic molecular junctions

“…1,0,1 exhibited maximum rectification of 3.43 at 1.6 V, whereas 1,1,0 and 1,1,1 assayed comparatively smaller values of 2.77 and 2.48 at 2 V, respectively. This bias-dependent rectification ratio was due to asymmetric evolution of the molecular orbitals [37] under positive and negative biases as shown in Figure 4. High forward current and low reverse current lead to high R(V), whereas low forward current and high reverse current lead to low R(V).…”

Odd‐Even Effects on Transport Properties of Polycyclic Arene Molecular Devices with Decreasing Numbers of Benzene Rings

“…To investigate the origin of the large rectification ratio of the device M1, Figure e shows the distribution of the electrostatic difference potential at zero bias. Generally speaking, the region with highest nonlinear electrostatic potential drop plays a leading role in the rectification behavior for molecular rectifiers . Obviously, the electrostatic potential of the device M1 is significantly asymmetric, leading to large a rectification behavior.…”

“…Generally speaking, the region with highest nonlinear electrostatic potential drop plays a leading role in the rectification behavior for molecular rectifiers. [39] Obviously, the electrostatic potential of the device M1 is significantly asymmetric, leading to large a rectification behavior. Additionally, the carbon atom attached to the molecule and ZGNR electrode on the right hand side has a higher potential drop, indicating that there appears to be a higher barrier at the region which plays an essential role in the electron transport properties.…”