Abstract: | We have measured the resistivity of NbSe3 doped with 5% Ta from room temperature down to 0.5K and compared our results with similar measurements on pure NbSe3. The pure sample remains normal to the lowest temperature (0.5K), whereas the doped sample has a sharp transition to the superconducting state with Tc = 1.5 ± 0.2 K. Measurements of the critical magnetic field indicate that the Ta doped samples are homogeneous, anisotropic three dimensional superconductors. |