Abstract: At ambient conditions, the compound CePd₂P₂ exists in the ThCr₂S₂ structure and orders ferromagnetically at 29 K. A combination of resistivity, magnetic susceptibility, and x-ray diffraction measurements were performed to examine the temperature-pressure-magnetic field phase diagram in CePd₂P₂. These results show that the ferromagnetic transition temperature is reduced by sustained mechanical pressure and abruptly drops to 0 K at approximately 12 GPa. We also compare our results to prior work by Lai et al. who studied the effects of chemical pressure produced via Pd-to-Ni substitution, finding that the transition temperature reaches 0 K at a cell volume of approximately 156 ų in both cases. 

The topological insulator Bi₂TeI and the topological metal Bi₃TeI show no signs of phase transitions between 2 and 300 K at ambient pressure. However, application of mechanical pressure through a diamond-anvil cell reveals a number of interesting properties in both compounds. Despite their different crystal structures at ambient pressure, x-ray diffraction reveals that both transition to a disordered bcc structure under sufficient pressure. Furthermore, resistivity and magnetic susceptibility measurements reveal superconductivity emerges at approximately 13 GPa in Bi2TeI and 11.5 GPa in Bi3TeI.