Tip-enhanced superconductivity in titanium

Abstract

We report a substantial enhancement of the superconducting transition temperature (Tc) in elemental titanium through mesoscopic point-contact formation using a simple needle–anvil technique. While bulk titanium exhibits Tc≈0.4 K under ambient conditions, our point-contact measurements reveal a locally induced superconducting phase with Tc values up to 3.5 K, comparable to that achieved under hydrostatic pressures of ∼56 GPa. The enhancement is highly contact dependent, indicating a local origin, likely associated with tip-induced uniaxial strain modifying the crystal and electronic structure beneath the contact. The evolution of resistance–temperature characteristics and differential conductance spectra with temperature and magnetic field yields an H–T phase diagram consistent with conventional superconductivity. Our results demonstrate a low-cost, table-top route to stabilizing superconducting phases with elevated Tc in elemental metals without resorting to extreme pressure techniques.