Related papers: Spin-orbital quantum liquid on the honeycomb latti…
Motivated by the recent synthesis of $\beta$-Li$_2$IrO$_3$ -- a spin-orbit entangled $j=1/2$ Mott insulator with a three-dimensional lattice structure of the Ir$^{4+}$ ions -- we consider generalizations of the Kitaev model believed to…
The simplest spin-orbital model can host a nematic spin-orbital liquid state on the triangular lattice. We provide clear evidence that the ground state of the SU(4) Kugel-Khomskii model on the triangular lattice can be well described by a…
One main theme in current condensed matter physics is the search of quantum spin liquid (QSL), an exotic magnetic state with strongly-fluctuating and highly-entangled spins down to zero temperature without static order. However, there is no…
By combining the density matrix renormalization group (DMRG) method with Gutzwiller projected wave functions, we study the SU(4) symmetric spin-orbital model on the honeycomb lattice. We find that the ground states can be well described by…
Spin liquids are novel states of matter with fractionalized excitations. A recent numerical study of Hubbard model on a honeycomb lattice\cite{Meng2010} indicates that a gapped spin liquid phase exists close to the Mott transition. Using…
Quantum spin liquids have been at the forefront of correlated electron research ever since their original proposal in 1973, and the realization that they belong to the broader class of intrinsic topological orders, along with the fractional…
The family of "Kitaev materials" provides an ideal platform to study quantum spin liquids and their neighboring magnetic orders. Motivated by the possibility of a quantum spin liquid ground state in pressurized hyperhoneycomb iridate…
We report the discovery of a novel gapless quantum spin liquid in the S=1 honeycomb system Cu$_3$LiRu$_2$O$_6$ with Ru$^{4+}$ ($4d^4$) where moments remain dynamic down to 50 mK. Heat capacity measurements show no sign of magnetic ordering…
A gas of strongly interacting spinless p-orbital fermionic atoms in 2D optical lattices is proposed and studied. Several interesting new features are found. In the Mott limit on a square lattice, the gas is found to be described effectively…
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…
In the field of quantum magnetism, the exactly solvable Kitaev honeycomb model serves as a paradigm for the fractionalization of spin degrees of freedom and the formation of $\mathbb{Z}_2$ quantum spin liquids. An intense experimental…
The absence of both spin freezing and of a static Jahn-Teller effect have lead to the proposition that Ba$_3$CuSb$_2$O$_9$ is a quantum spin-orbital liquid. However, theoretical understanding of the microscopic origin of this behavior has…
The possible emergence of a spin liquid phase in the half-filled Hubbard model on the honeycomb lattice; a simple model of graphene, is studied using the variational cluster approximation. We found that the critical interaction strength of…
We construct a physically realistic and analytically tractable model for spin-1 systems with orbital degeneracy on the honeycomb lattice, relevant to honeycomb materials with large Hund's and weak spin-orbit couplings, and two electrons in…
We construct a tight-binding model of [(C$_2$H$_5$)$_3$NH]$_2$Cu$_2$(C$_2$O$_4$)$_3$ from Wannier orbital overlaps. Including interactions within the Jahn-Teller distorted Cu-centered $e_g$ Wannier orbitals leads to an effective Heisenberg…
We perform a projective symmetry group classification of spin $S=1/2$ symmetric quantum spin liquids with different gauge groups on the diamond lattice. Employing the Abrikosov fermion representation, we obtain $8$ $SU(2)$, $62$ $U(1)$ and…
Recent experiments suggest a quantum spin liquid ground state in the material PbCuTe$_2$O$_6$, where $S=1/2$ moments are coupled by antiferromagnetic Heisenberg interactions into a three dimensional structure of corner sharing triangles…
The nature of the effective spin Hamiltonian and magnetic order in the honeycomb iridates is explored by considering a trigonal crystal field effect and spin-orbit coupling. Starting from a Hubbard model, an effective spin Hamiltonian is…
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…
Motivated by the absence of cooperative Jahn-Teller effect in LiNiO2 and BaVS3, two layered oxides with triangular planes, we study the SU(4) symmetric spin-orbital model on the triangular lattice. Upon reducing the next-nearest neighbour…