Institute of High Pressure Physics

In the recent study, Prof. Singh’s research team has investigated the effect of “spark plasma sintering (SPS)” process on the superconducting properties of iron-based superconductors in collaboration with Shibaura Institute of Technology (SIT), Japan. They have also conducted a comparative analysis of conventional, high-gas-pressure, and SPS techniques to understand their impact on superconducting properties. Interestingly, the SPS process increased the critical current density without significantly affecting the critical transition temperature, which is attributed to the enhanced density of the samples. More details about this study can be found in the published paper by: Mohammad Azam, Tatiana Zajarniuk, Konrad Kwatek, Paolo Mele, and Shiv J. Singh entitled “Effect of spark plasma sintering on the superconducting properties of Sm-based oxypnictide” Cryogenics 150, 104125 (2025) (Elsevier); https://doi.org/10.1016/j.cryogenics.2025.104125

Figure: The variations of (a) the onset transition temperature (T_c^onset), (b) the transition width (ΔT), (c) the room temperature resistivity (ρ_{300 K}), (d) the Residual Resistance Ratio (RRR = ρ_{300 K} / ρ_{60 K}), and (e) the critical current density (J_c) of different SmFeAsO_0.80F_0.20 bulks prepared by conventional (0 MPa), high gas pressure (500 MPa) and SPS (45 MPa) processes under the different growth pressures.