Shear Strain in Nd0.5 Ca0.5 MnO₃ at High Pressures

Titelangaben

Arulraj, Anthony ; Dinnebier, Robert E. ; Carlson, Stefan ; Hanfland, Michael ; van Smaalen, Sander:
Shear Strain in Nd0.5 Ca0.5 MnO₃ at High Pressures.
In: Physical Review Letters. Bd. 94 (2005) . - 165504.
ISSN 1079-7114
DOI: https://doi.org/10.1103/PhysRevLett.94.165504

Volltext

Link zum Volltext (externe URL):

Abstract

High-pressure x-ray powder diffraction has been measured on the half doped rare earth manganite Nd0.5Ca0.5MnO3 up to a pressure of 15 GPa. We report the presence of a quantifiable amount of shear distortion of the MnO6 octahedra in Nd0.5Ca0.5MnO3 at high pressures. The lattice strain of Nd0.5Ca0.5MnO3 is minimal at a crossover pressure of p∗∼7  GPa, with the same lattice strain above and below this pressure achieved by shear and Jahn-Teller–type distortions, respectively. The increase in shear strain with increasing pressure provides a mechanism for the insulating behavior of manganites at high pressures that has not been considered before.