Weak localization and electron–electron interaction induce resistance minimum in 2H-Ga_0.20NbSe₂

Here we present the resistivity on polycrystalline compounds of 2H-Ga_xNbSe₂ where x = 0 and 0.20 in the temperature range $2⩽T⩽300K.$ The 2H-NbSe₂ shows the superconducting (SC) state at T _s = 7.4 K whereas 2H-Ga_0.20NbSe₂ shows a minimum in resistivity 'ρ _min' at T _min = 18 K followed by a rapid decrease in resistivity below 4 K. This resistivity minimum in 2H-Ga_0.20NbSe₂ has been discussed by two models namely weak localization and electron–electron interaction. Though $\Delta \rho /{\rho }_{min}$ is well fitted by $\sqrt{T}$ law in 2H-Ga_0.20NbSe₂ associated with electron–electron scattering, there is also a contribution from spin–orbit scattering to the rise in resistivity below 18 K due to weak localization found from MR measurement. (paper)