Electronic and structural properties of rhombohedral [1 1 1] and [1 1 0] oriented ultra-thin bismuth nanowires.

Title Electronic and structural properties of rhombohedral [1 1 1] and [1 1 0] oriented ultra-thin bismuth nanowires.
Authors Ansari, L.; Gity, F.; Greer, J.C.
Journal J Phys Condens Matter
DOI 10.1088/1361-648X/aa4e63
Abstract

Structures and electronic properties of rhombohedral [1 1 1] and [1 1 0] bismuth nanowires are calculated with the use of density functional theory. The formation of an energy band gap from quantum confinement is studied and to improve estimates for the band gap the GW approximation is applied. The [1 1 1] oriented nanowires require surface bonds to be chemically saturated to avoid formation of metallic surface states, whereas the surfaces of the [1 1 0] nanowires do not support metallic surface states. It is found that the onset of quantum confinement in the surface passivated [1 1 1] nanowires occurs at larger critical dimensions than for the [1 1 0] nanowires. For the [1 1 1] oriented nanowires it is predicted that a band gap of ~0.5 eV can be formed at a diameter of approximately 6 nm, whereas for the [1 1 0] oriented nanowires a diameter of approximately 3 nm is required to achieve a similar band gap energy. The GW correction is also applied to estimates of the electron affinity, ionisation potentials and work functions for both orientations of the nanowires for various diameters below 5 nm. The magnitude of the energy band gaps that arise in bismuth at critical dimensions of a few nanometers are of the same order as for conventional bulk semiconductors.

Citation Ansari, L.; Gity, F.; Greer, J.C..Electronic and structural properties of rhombohedral [1 1 1] and [1 1 0] oriented ultra-thin bismuth nanowires..

Related Elements

Bismuth

See more Bismuth products. Bismuth (atomic symbol: Bi, atomic number: 83) is a Block P, Group 15, Period 6 element with an atomic radius of 208.98040. The number of electrons in each of Bismuth's shells is 2, 8, 18, 32, 18, 5 and its electron configuration is [Xe] 4f14 5d10 6s2 6p3. Bismuth Bohr ModelThe bismuth atom has a radius of 156 pm and a Van der Waals radius of 207 pm. In its elemental form, bismuth is a silvery white brittle metal. Bismuth is the most diamagnetic of all metals and, with the exception of mercury, its thermal conductivity is lower than any other metal. Elemental BismuthBismuth has a high electrical resistance, and has the highest Hall Effect of any metal (i.e., greatest increase in electrical resistance when placed in a magnetic field). Bismuth is found in bismuthinite and bismite. It is also produced as a byproduct of lead, copper, tin, molybdenum and tungsten extraction. Bismuth was first discovered by Early Man. The name Bismuth originates from the German word 'wissmuth,' meaning white mass.