Abstract
Using the density matrix renormalization group technique we study the effect of spin-orbit coupling on a three-orbital Hubbard model in the (t2g)4 sector and in one dimension. Fixing the Hund coupling to a robust value compatible with some multiorbital materials, we present the phase diagram varying the Hubbard U and spin-orbit coupling λ, at zero temperature. Our results are shown to be qualitatively similar to those recently reported using the dynamical mean-field theory in higher dimensions, providing a robust basis to approximate many-body techniques. Among many results, we observe an interesting transition from an orbital-selective Mott phase to an excitonic insulator with increasing λ at intermediate U. In the strong U coupling limit, we find a nonmagnetic insulator with an effective angular momentum ((Jeff)2)≠0 near the excitonic phase, smoothly connected to the ((Jeff)2)=0 regime. We also provide a list of quasi-one-dimensional materials where the physics discussed in this paper could be realized.
| Original language | English |
|---|---|
| Article number | 155111 |
| Journal | Physical Review B |
| Volume | 96 |
| Issue number | 15 |
| DOIs | |
| State | Published - Oct 9 2017 |
Funding
The authors acknowledge useful conversations with Prof. G. Cao. N.K. was supported by the National Science Foundation Grant No. DMR-1404375. J.H, A.N., A.M., F.R., and E.D. were supported by the US Department of Energy (DOE), Office of Basic Energy Sciences (BES), Materials Sciences and Engineering Division. The work of G.A. was conducted at the Center for Nanophase Materials Science, sponsored by the Scientific User Facilities Division, BES, DOE, under contract with UT-Battelle.