Abstract
The competition between Kitaev and Heisenberg interactions away from half filling is studied for the hole-doped Kitaev-Heisenberg -- model on a honeycomb lattice. While the isotropic Heisenberg coupling supports a time-reversal violating -wave singlet state, we find that the Kitaev interaction favors a time-reversal invariant -wave superconducting phase, which obeys the rotational symmetries of the microscopic model, and is robust for . Within the -wave superconducting phase, a critical chemical potential separates a topologically trivial phase for from a topologically nontrivial time-reversal invariant spin-triplet phase for .
- Received 6 October 2011
DOI:https://doi.org/10.1103/PhysRevB.85.140510
©2012 American Physical Society