Pressure effect on the electrical properties and pressure-induced phase transitions in a three-dimensional Dirac semimetal BaAgBi

High pressure is an effective and clean method for tuning lattice structures and electronic states. In this study, we report on the crystal growth and experimental study of the pressure effect on the three-dimensional Dirac semimetal BaAgBi. Within the pressure range of 51.8 GPa studied in this work, BaAgBi remained metallic and no superconductivity was observed down to 1.6 K. The resistance is primarily governed by the electron-phonon and s-d electron-electron scattering. High-pressure synchrotron X-ray diffraction experiments indicated the presence of two high-pressure phases below 50 GPa, and the crystal structures were proposed to be Pnma and Pca21, respectively. By refining the high-pressure X-ray data, we plotted the pressure dependence of unit cell volumes and obtained the bulk modulus for all three phases.