Abstract
Neutron single-crystal diffraction and rotational anisotropy optical second harmonic generation data are presented resolving the nature of the structural distortion realized in electron-doped (Sr1-xLax)3Ir2O7 with x=0.035 and x=0.071. Once electrons are introduced into the bilayer spin-orbit assisted Mott insulator Sr3Ir2O7, previous studies have identified the appearance of a low-temperature structural distortion and have suggested the presence of a competing electronic instability in the phase diagram of this material. Our measurements resolve a lowering of the structural symmetry from monoclinic C2/c to monoclinic P21/c and the creation of two unique Ir sites within the chemical unit cell as the lattice distorts below a critical temperature TS. Details regarding the modifications to oxygen octahedral rotations and tilting through the transition are discussed as well as the evolution of the low-temperature distorted lattice as a function of carrier substitution.
Original language | English |
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Article number | 174109 |
Journal | Physical Review B |
Volume | 95 |
Issue number | 17 |
DOIs | |
State | Published - May 30 2017 |