Shockwave-loading-induced Enhancement Of Properties In Superconducting Bi₂Sr₂CaCu₂O_8+δ

Improving the critical transition temperature of high temperature superconducting materials has always been a research hotspot in the field of materials science.Bi₂Sr₂CaCu₂O_8+δ（Bi2212）is a prototypical high-temperature superconductor that has been widely studied due to its excellent characteristics such as high critical transition temperature,good plasticity and easy processing.In this work,a novel method for altering the properties of the superconductor material Bi₂Sr₂CaCu₂O_8+δ（Bi2212）is reported.After shockwave treatment,several techniques were used in combination to characterize the treated Bi2212 sample,including X-ray diffraction（XRD）,transmission electron microscopy（TEM）,four probe method for measuring resistance,and superconducting quantum interference device（SQUID）magnetometry.It is found that the superconducting transition temperature（Tc）increases from 84 K for the pristine sample to 94 K for the sample treated at a high temperature and a high pressure,respectively.XRD and TEM characterizations indicate that this Tc enhancement arises from a phase transition from pristine Bi2212 to a mixture of superconducting Bi2212 and semiconducting Bi₂Sr₂CuO_6+δ（Bi2201）during the shockwave treatment.The shockwave-treated sample exhibits n-type semiconductor properties（with an on-off ratio ⁵）,in contrast to the pure metallic pristine sample.The study offers an alternative route for modifying the superconducting properties via a shockwave treatment.Furthermore,this method may provide a new approach for studying other temperature-and pressure-sensitive materials.