Electrical resistivity of gallium single crystals at low temperatures

Abstract

Electrical resistivity measurements on single crystals of gallium grown to conform approximately to the three axial directions have been extended to low temperatures, detailed investigation being made over the range 20.4 to 4.2° K. The anisotropy of this property increases in this region where the resistivity ratios for the three specimens are approximately 1: 2.1: 8 compared with 1: 2.1 6 : 6.5 5 at room temperature. The ‘ideal’ resistivity is proportional to T n , where n ≃ 4.45 for the range 5 to 12° K and decreases to about 3.9 for the range 12 to 20.4° K. The characteristic temperatures as derived from Grüneisen’s expression show relatively small differences for the three axial directions but decrease with decrease in temperature. Comparable variations with temperature are observed in the characteristic temperatures derived previously from specific heat measurements on gallium.