Abstract
We have fabricated superconducting samples comprising gallium (Ga) or zinc (Zn) infiltrated into the one-dimensional (1D) linear channels of AlPO-5 (AFI) zeolite, which have an internal pore diameter of 7 Å and are separated by an insulating wall of ∼7–9 Å. The Angstrom-scale Ga and Zn sub-nanowires, arranged in Josephson-coupled triangular arrays with an ab-plane lattice constant of 14.4 Å, display bulk superconductivity with Tc values of 7.2 K and 3.7 K, respectively, which are significantly enhanced by a factor of 7 and 4 compared with their bulk values. While the zeolite template of our composite superconductor dictates the nanostructure of Ga and Zn to be 1D in the electronic sense with a highly advantageous effect for the superconducting pairing, the arrangement in a densely packed array structure avoids the shortcomings of other typical 1D superconductors, in which the coherence is usually completely suppressed by strong phase fluctuations.
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•We have fabricated first sub-nanometer scale gallium (Ga) and zinc (Zn) nanowires.•Enhancement of Ga and Zn superconducting transition temperature by 7 and 4 times.•Big critical magnetic field enhancement for Ga and Zn nanowires@zeolite composite.