Transport properties of antimony nanowires

Abstract

This paper reports the temperature dependence of the resistivity and the longitudinal and transverse magnetoresistance of antimony quantum wires with diameters ranging from 200 down to 10 nm. The samples were prepared in porous anodic alumina host materials using the vapor-phase technique. A theoretical calculation of the band structure of Sb nanowires is presented and a transport model for nanowire systems is used to explain the measured temperature dependence of the resistivity, showing both classical and quantum finite-size effects. The magnetoresistance is quadratic at low fields. In the 200 nm wires, the low-temperature (T,50 K) longitudinal magnetoresistance exhibits a maximum at the magnetic field where the cyclotron radius roughly corresponds to the wire radius. Surface scattering dominates below that field, and bulklike scattering dominates above it. In the narrower wires, the low-temperature ~below 10 K for 50 nm wires and below 40 K for 10 nm wires! magnetoresistance shows a steplike feature at the critical magnetic field where the magnetic length equals the wire diameter, as was the case for bismuth wires. This phenomenon is independent of the effective masses, depending only on the geometry of the nanowires and on the magnetic flux in the wire, and it is therefore attributed to a localization effect.