Transport Properties Of Boron Research Articles

Electronic and transport properties of boron and nitrogen passivated zigzag graphene nanoribbons

A systematic study is conducted on 8ZGNR by edge terminations with boron and nitrogen at I and II termination sites by replacing hydrogen atoms in a single layer and in two probe systems. Electronic properties were observed in the DFT framework. Non-equilibrium green’s function (NEGF) tool was used to study the transport properties. Analysis of band structure, total energy, formation energy, and projected density of states (PDOS) suggest that despite Boron and Nitrogen passivation at all the termination sites, the electronic behavior of the system remains metallic. The analysis of Transmission spectra also confirms its metallic behavior in all these cases. This study reveals that B and N passivated graphene nanoribbons are sensitive to electronic transmission. This fact makes it potentially useful for application in sensors, memory devices and many other nano-electronic devices.

Electronic and transport properties of boron- and nitrogen-rich graphene nanoribbons based on coronene-like units

Several graphene nanoribbon forms have been obtained from the fusion of different molecular precursors over the last decade. These include a rich set of examples in which heteroatoms substitute carbon at precisely defined sites. Considering this scenario, we employed first-principles calculations to study the electronic and transport properties of coronene-based nanoribbons with boron and nitrogen heteroatoms. We demonstrate that B/N substitution induces marked changes in the electronic properties of these structures in comparison to the full-carbon counterpart. For instance, the systems change from semiconductor to metallic due to levels introduced by the heteroatoms. In addition, non-trivial spin-polarized distributions emerge in selected cases, resulting in systems with a high potential for insertion in spintronic applications. This is further investigated in nanojunctions composed of N-substituted electrodes.

Electronic and transport properties of boron and nitrogen doped germanene nanoribbons: A first principles study

We have studied the electronic properties of pristine zigzag germanene nanoribbons (ZGeNRs) using ab initio method. The effect of boron and nitrogen doping on electronic properties of ZGeNRs at two different edge sites is also calculated. It is observed that the H-terminated pristine ZGeNRs exhibit semi-metallic behavior while the ZGeNRs doped with boron and nitrogen shows the metallic behavior. The electron density calculation shows that the density is low in pristine ZGeNRs while it is high in the doped ZGeNRs. The transmission coefficient analysis also suggests the same. As the transmission is sensitive to doping, hence, ZGeNRs have potential application in nanoelectronics devices.

Electronic and transport properties of boron and nitrogen doped graphene nanoribbons: an ab initio approach

Graphene nanoribbons (GNRs) are expected to display extraordinary properties in the form of nanostructures. The effect of boron and nitrogen substitutional doping at four successive positions on electronic and transport properties of zigzag graphene nanoribbons (ZGNRs) is studied using spin-unpolarized density functional theory. It has been observed that the electronic structures of the doped ZGNRs are different from those of pristine ZGNRs. We have also calculated the transformation energy in the form of total energy. The substitutional boron atom at the nanoribbons edges suppresses the energy band near Fermi level by changing properties of material from metallic to semi-metallic in ZGNRs which can be explained as a consequence of the edge polarization effects. At all doping positions, N-doped ZGNRs are n-type while B-doped ZGNRs are p-type semiconductors. These substitutionally B- and N-doped impurities act as scattering centers for transport in GNRs. Due to unusual properties of these nanomaterials, they can be used in carbon-based nanoelectronics devices.

Experiments and simulations on hot expanded boron

We measured the thermodynamical and transport properties of boron in the warm dense matter regime ( 15000 K<T<25000 K and rho=0.094 g/cm3). Experimental data are compared with quantum molecular dynamics (QMD) simulations. We find a very good agreement between data and calculations, which permits us to transform experimental energies into temperatures, and allows us to compare conductivities with an average atom model coupled with a Kubo-Greenwood calculations. Contact is made between computationally intensive QMD simulation codes and fast average atom models.

Surface Segregation and Backscattering in Doped Silicon Nanowires

By means of ab initio simulations, we investigate the structural, electronic, and transport properties of boron and phosphorus doped silicon nanowires. We find that impurities always segregate at the surface of unpassivated wires, reducing dramatically the conductance of the surface states. Upon passivation, we show that for wires as large as a few nanometers in diameter, a large proportion of dopants will be trapped and electrically neutralized at surface dangling bond defects, significantly reducing the density of carriers. Important differences between p- and n-type doping are observed. Our results rationalize several experimental observations.

Transport properties of boron and aluminum

Transport cross sections and collision integrals are tabulated for a wide range of energies and temperatures for the interactions B–B and Al–Al. For aluminum, a semiclassical approximation was used to determine the scattering phase shifts from which the transport cross sections were calculated. For boron, the smaller reduced mass and the deep potential wells required the phase shifts at lower energies to be determined from a numerical solution of the time-independent Schroedinger equation; the semiclassical approximation was used at higher energies where the two methods agree. The variations of the collision integrals for viscosity and diffusion are presented graphically as a function of temperature. The results are applied to estimate the transport properties of gallium.