Superconducting tunneling study of vanadium

The tunneling spectroscopy of McMillan and Rowell is extended to vanadium, with the use of clean and highly ordered structures of the form M- Al₂{O}₃$-Al/V. The Eliashberg function ${{α}}²F(E)$ is determined and leads to ${λ}=0.82±{}0.05$ and ${{μ}}ₚₕ*=0.15±{}0.03$. These tunneling results, the first available for V, indicate a smaller influence of paramagnon spin fluctuations in suppressing superconductivity in vanadium than recently suggested, but do not rule out such effects at a level λₛ~0.1.