Competing exotic topological insulator phases in transition-metal oxides on the pyrochlore lattice with distortion

  title={Competing exotic topological insulator phases in transition-metal oxides on the pyrochlore lattice with distortion},
  author={Mehdi Kargarian and Jun Wen and Gregory A. Fiete},
  journal={Physical Review B},
In this work we investigate the phase diagram of heavy (4d and 5d) transition metal oxides on the pyrochlore lattice, such as those of the form $\mathrm{A_2M_2O_7}$, where A is a rare earth element and M is a transition metal element. We focus on the competition between Coulomb interaction, spin-orbit coupling, and lattice distortion when these energy scales are comparable. Strong spin-orbit coupling entangles the spin and the $t_{2g}$ $d$-orbitals giving rise to doublet $j=1/2$ and quadruplet… Expand

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