Flux Pinning Properties in BaHfO3-Doped $\mbox{SmBa}_{2}\mbox{Cu}_{3}\mbox{O}_{y}$ Films on Metallic Substrates Fabricated With Low Temperature Growth
We have developed SmBa2Cu3Oy (SmBCO) superconducting films with BaHfO3 (BHO) inclusions on singlecrystalline substrates via a pulsed laser deposition method. We have controlled the morphology of the BHO nanorods within the SmBCO matrix by varying growth temperature during the depositions. In this paper, we fabricated 1.5 vol.% BHO-doped SmBCO films on metallic substrates at 750 °C [low-temperature growth (LTG) film] and 840 °C [high-temperature growth (HTG) film]. The LTG film showed lower flux pinning performance at a relatively high measurement temperature ranging from 65 K to 77 K than the HTG film. However, at a low measurement temperature of 20 K under high magnetic fields, the LTG film exhibited higher flux pinning performance in comparison with the HTG film. The maximum flux pinning force density was more than 520 GN/m3 at 20 K under 9 T. Even on the metallic substrates, LTG is also helpful in achieving an improved flux pinning performance of SmBCO films at low measurement temperatures under high magnetic fields.