Large magnetoresistance effect in thin bismuth wires

Large transverse-magnetoresistance (MR) ratios, r = AR(H, T)/R(0, T), have been observed in Bi single-crystal wires fabricated by the glass-coated melt-spinning method. It was found that at T = 300 K and H = 140 kOe (H∥C 3 ), the wires with diameters of 1.6, 3.0 and 10.0 μm and zero-field resistances of 3250, 805 and 66 Ω have increasing MR values of 10.2, 11.9 and 14.3. For H⊥C 3 , we obtained r = 15.2 for the 3-μm wire. At lower temperatures, the magnitude of the MR effect is much larger and lies in the ranges 300-1660 at 77 K and 2000-3500 at 4.2 K. It was shown that for some directions of the magnetic field with respect to Bi crystal axes, the MR curves do not saturate up to 140kOe at any temperature.