SU(4) Heisenberg model on the honeycomb lattice with exchange-frustrated perturbations: implications for twistronics and Mott insulators.
NATORI, Willian Massashi Hisano; NUTAKKI, R.; PEREIRA, R. G.; ANDRADE, Eric de Castro e.
NATORI, Willian Massashi Hisano; NUTAKKI, R.; PEREIRA, R. G.; ANDRADE, Eric de Castro e.
 Abstract: The SU(4)-symmetric spin-orbital model on the honeycomb lattice was recently studied in connection to correlated insulators such as the eg Mott insulator Ba3CuSb2O9 and the insulating phase of magic-angle twisted bilayer graphene at quarter filling. Here we provide a unified discussion of these systems by investigating an extended model that includes the effects of Hund?s coupling and anisotropic, orbital-dependent exchange interactions. Using a combination of mean-field theory, linear flavor-wave theory, and variational Monte Carlo, we show that this model harbors a quantum spin-orbital liquid over a wide parameter regime around the SU(4)-symmetric point. For large Hund?s coupling, a ferromagnetic antiferro-orbital ordered state appears, while a valence-bond crystal combined with a vortex orbital state is stabilized by dominant orbital-dependent exchange interactions. | |
| Physical Review B |
| v. 100, n. 20, p. 205131-1-205131-10 - Ano: 2019 |
| Fator de Impacto: 3,736 |
| http://dx.doi.org/10.1103/PhysRevB.100.205131 |  @article={002980098,author = {NATORI, Willian Massashi Hisano; NUTAKKI, R.; PEREIRA, R. G.; ANDRADE, Eric de Castro e.},title={SU(4) Heisenberg model on the honeycomb lattice with exchange-frustrated perturbations: implications for twistronics and Mott insulators},journal={Physical Review B},note={v. 100, n. 20, p. 205131-1-205131-10},year={2019}} |