Pressure-induced transitions in single-crystal La0.84Sr0.16MnO3

Measurements of the transport properties under high pressure of an x=0.16 crystal have revealed the disappearance, in a two-phase domain, of a low-temperature, orbitally ordered O'' phase, as well as a discontinuous crossover of the ferromagnetic Curie temperature T_c at an orthorhombic-rhombohedral phase boundary in the narrow compositional range 0.16<x<0.17 of the system La_1-xSr_xMnO₃. The data also suggest that the O'' phase below an insulator-metal transition temperature T_IM is distinguishable from that between the order-disorder transition at T_oo.