Pressure-induced enhancement of non-polar to polar transition temperature in metallic LiOsO_3

摘要

LiOsO3 undergoes a continuous transition from a centrosymmetric R (3) over barc structure to a polar R3c structure at T-s = 140 K. By combining transport measurements and first-principles calculations, we find that T-s is enhanced by applied pressures, and it reaches a value of similar to 250K at similar to 6.5 GPa. The enhancement is due to the fact that the polar R3c structure of LiOsO3 has a smaller volume than the centrosymmetric R (3) over barc structure. Pressure generically favors the structure with the smallest volume, and therefore further stabilizes the polar R3c structure over the R (3) over barc structure, leading to the increase in Ts. Published by AIP Publishing.