Improvement in the width of superconducting transition ΔT c of Nb3Ge by small mechanical shock

A small mechanical shock (∼10 kPa) was applied to sputtered Nb3Ge films at room temperature. The superconducting transition temperature Tc of the films has been measured, and remeasured after application of the shock. The results confirm that the small mechanical shock improves Tc and Tce (lower onset) markedly. Changes in the lattice parameter and improvement in the structural ordering of the high-Tc A-15 phase after application of the shock have been observed from the results of x-ray measurements.