Analysis of temperature dependencies of transport coefficients for a single-crystal bismuth wire with a 1.90-μm diameter

Abstract

We measured the temperature dependencies of resistivity, Seebeck coefficient, magnetoresistivity, and Hall coefficient from 20 to 300 K for an individual single-crystal bismuth wire with a diameter of 1.90  μm and a length of 1554  μm. The wire was embedded in a quartz glass after making local electrodes on the wire through a nanofabrication process. The temperature dependencies were investigated using a model that considered not only the wire diameter, crystal orientation, band structure, and Fermi surface of the bismuth, but also the scattering process and mean free path of the carrier. We were able to explain the dependencies of resistivity and Seebeck coefficient on the contribution of each carrier pocket for the bismuth wire. The results showed that the specific conductivity of the carrier pocket of bismuth was dominant in the lower temperature region due to the wire geometry. As a result, the characteristic temperature dependence of resistivity was observed. Furthermore, the temperature dependence of the Hall coefficient was estimated using conductivity, and the data indicated that the experimental and calculation results were in good agreement.