Novel interplay of spin-orbit coupling and electron correlations in complex Ir oxides recently emerged as a new paradigm for correlated electron physics. Because of a large spin-orbit coupling of ~0.5 eV, which is comparable to the transfer energy t and the crystal field splitting Δ and Coulomb U, a variety of ground states including magnetic insulator, band insulator, semimetal and metal, shows up in a narrow materials phase space. Utilizing such subtle competition of the ground states, we successfully tailor a spin-orbital magnetic insulator out of a semimetal SrIrO3 by controlling dimensionality using superlattice of [(SrIrO3)m, SrTiO3] and show that a magnetic ordering triggers the transition to magnetic insulator. Those results can be described well by a first-principles calculation. This study is an important step towards the design and the realization of topological phases in complex Ir oxides with very strong spin-orbit coupling.
@article{arxiv.1401.1066,
title = {Engineering spin-orbital magnetic insulator by tailoring superlattices},
author = {Jobu Matsuno and Kota Ihara and Shugen Yamamura and Hiroki Wadati and Kenji Ishii and V. Vijay Shankar and Hae-Young Kee and Hidenori Takagi},
journal= {arXiv preprint arXiv:1401.1066},
year = {2015}
}