Resistance and Magnetoresistance of Thin Indium Wires

Abstract

The resistances of indium wires of diameter ranging between 0.642 and 0.0156 mm were measured at regular temperature intervals between 1.2 and 4.2°K and in transverse magnetic fields up to 18 kG. The bulk resistivity at 4.2°K, ${\rho }_b\mathrm{}\left(4.2\right)=(0.93\mathrm{}\pm 0.03)\times {10}^{-9\mathrm{}} \Omega$ cm, and bulk mean free path, $l_b\mathrm{}\left(4.2\right)=(1.61\mathrm{}\pm 0.08)\times {10}^{-2\mathrm{}}$ cm, deduced from our data agree with other recent measurements, as does the average Fermi momentum, $p_F=(1.0\mathrm{}\pm 0.15)\times {10}^{-19\mathrm{}}$ g cm/sec, determined from observations of the MacDonald—Sarginson effect. Size-dependent deviations from Kohler's rule suggest that a new magnetoresistive mechanism may be effective in wires of very small diameter ($d<\mathrm{}0.08\mathrm{}$ mm). Comparison of the product ${\rho }_b{l}_b$ at 4.2 and 0°K shows evidence of the size- and temperature-dependent resistivity contribution observed previously in indium and a number of other metals.