Related papers: Exploring the spin-orbital ground state of Ba3CuSb…
We discuss the ground state of the spin-orbital model for spin-one ions with partially filled $t_{2g}$ levels on a honeycomb lattice. We find that the orbital degrees of freedom induce a spontaneous dimerization of spins and drive them into…
Structure with orbital degeneracy is unstable toward spontaneous distortion. Such orbital correlation usually has a much higher energy scale than spins, and therefore, magnetic transition takes place at a much lower temperature, almost…
Dynamical Jahn-Teller (DJT) effect in a spin-orbital coupled system on a honeycomb lattice is examined, motivated from recently observed spin-liquid behavior in Ba$_3$CuSb$_2$O$_9$. An effective vibronic Hamiltonian, where the superexchange…
A spin liquid is a novel quantum state of matter with no conventional order parameter where a finite charge gap exists even though the band theory would predict metallic behavior. Finding a stable spin liquid in two or higher spatial…
Stabilizing exotic quantum phases of matter, e.g. spin liquid, is an attractive topic in condensed matter. Here, by a Monte Carlo study of a two-orbital spin-fermion model on a honeycomb lattice, we show the cooperative effects of the…
We study the effective spin-orbital model that describes the magnetism of 4$d^1$ or 5$d^1$ Mott insulators in ideal tricoordinated lattices. In the limit of vanishing Hund's coupling, the model has an emergent SU(4) symmetry which is made…
We study the zero-temperature quantum phase diagram of a spin-1 Heisenberg antiferromagnet on the honeycomb lattice with both nearest-neighbor exchange coupling $J_{1}>0$ and frustrating next-nearest-neighbor coupling $J_{2} \equiv \kappa…
We study the interplay between spin-orbit coupling (SOC) and Coulomb repulsion in a Hubbard model on a decorated honeycomb lattice which leads to a plethora of phases. While a quantum spin hall insulator is stable at weak Coulomb repulsion…
We use a projective symmetry group analysis to determine all symmetric spin liquids on the stuffed honeycomb lattice Heisenberg model. This lattice interpolates between honeycomb, triangular and dice lattices, always preserving hexagonal…
We explore orbital dynamics in the spin liquid candidate Ba3CuSb2O9 using multi-frequency electron spin resonance. We prepared two high quality single crystals. The crystal with a slight copper deficiency shows a structural phase transition…
We explore the magnetic properties of isolated a-b planes of trinuclear organometallic crystals, Mo3S7(dmit)3, in which an interplay of strong electronic correlations and spin molecular-orbital coupling (SMOC) occurs. The magnetic…
We study the effective spin-orbital model for honeycomb-layered transition metal compounds, applying the second-order perturbation theory to the three-orbital Hubbard model with the anisotropic hoppings. This model is reduced to the Kitaev…
Recent numerical work (Nature 464, 847 (2010)) indicates the existence of a spin liquid phase (SL) that intervenes between the antiferromagnetic and semimetallic phases of the half filled Hubbard model on a honeycomb lattice. To better…
Inspired by recent measurements on Ba$_3$CuSb$_2$O$_9$, we explore the interplay of spin and orbital degrees of freedom in a triangular lattice for possible spin liquid-like behaviour. Our effective Hamiltonian describes the magnetic Cu…
We investigate the interplay between spin-orbit coupling and electron-electron interactions on the honeycomb lattice combining the cellular dynamical mean-field theory and its real space extension with analytical approaches. We provide a…
We report a muon spin rotation/relaxation ($\mu$SR) study of single-crystalline samples of the $\alpha$-RuCl$_3$ honeycomb magnet, which is presumed to be a model compound for the Kitaev-Heisenberg interaction. It is inferred from magnetic…
Motivated by the rich physics of honeycomb magnetic materials, we obtain the phase diagram and analyze magnetic properties of the spin-1/2 and spin-1 J1-J2-J3 Heisenberg model on the honeycomb lattice. Based on the SU(2) and SU(3) symmetry…
In this paper we analyze the groundstate and finite-temperature properties of a frustrated Heisenberg $J_1-J_2$ model on a honeycomb lattice by employing the Schwinger boson technique. The phase diagram and spin gap as functions of…
The layered RuBr3-RuI3 honeycomb system was synthesized at high-pressures. The crystal structures are centrosymmetric (space group R-3), and based on honeycomb layers of Ru$^{3+}$ (S=1/2). Their basic physical properties are surveyed. The…
Intensive studies of the interplay between spin-orbit coupling (SOC) and electronic correlations in transition metal compounds have recently been undertaken. In particular, $j_{\rm eff}$ = 1/2 bands on a honeycomb lattice provide a pathway…