Related papers: Magnetically ordered yet topologically robust phas…
The higher-spin Kitaev magnets, in which the Kitaev interaction and off-diagonal exchange couplings are overwhelmingly large, have emerged as a fertile avenue to explore exotic phases and unusual excitations. In this work, we study the…
We report the existence of a phase transition at high temperature in the 3D Kitaev candidate material, $\beta$-Li$_2$IrO$_3$. We show that the transition is bulk, intrinsic and orders a tiny magnetic moment with a spatially anisotropic…
There have been intensive studies on Kitaev materials for the sake of the realization of exotic states such as quantum spin liquid and topological orders. In realistic materials, the Kitaev interaction may coexist with the…
Frustrated quantum magnets may exhibit fascinating collective phenomena. The main goal of this dissertation is to provide conclusive evidence for the emergence of novel phases of matter like quantum spin liquids in local quantum spin…
We present a spin model, namely, the Kitaev model augmented by a loop term and perturbed by an Ising Hamiltonian and show that it exhibits both confinement-deconfinement transitions from spin liquid to…
Kitaev iridates have been proposed as candidates for realizing an elusive quantum spin liquid (QSL) state, in which strong spin-orbit coupling and bond-directional exchange generate a highly frustrated and entangled ground state. However,…
Recently, realizations of Kitaev physics have been sought in the A2IrO3 family of honeycomb iridates, originating from oxygen-mediated exchange through edge-shared octahedra. However, for the j = 1/2 Mott insulator in these materials…
The competing spin orders and fractional magnetization plateaus of classical Heisenberg model with long-range interactions on a Shastry-Sutherland lattice are investigated using Monte Carlo simulations, in order to understand the…
We report the finding of a series of symmetry distinct spin liquid (SL) states and a rich phase diagram in a half-filled honeycomb lattice Hubbard model with spin-dependent hopping amplitude t'. We first study the magnetic instability of…
Magnetic skyrmions, topologically stable spin textures, have attracted significant interest due to their potential applications in information storage and processing. They are typically stabilized by the Dzyaloshinskii-Moriya interaction in…
The stability of the topological order phase induced by the $Z_3$ Kitaev model, which is a candidate for fault-tolerant quantum computation, against the local order phase induced by the 3-State Potts model is studied. We show that the low…
Spin-orbit coupling introduces chirality into electronic structure. This can have profound effects on the magnetization induced by orbital motion of electrons. Here we derive a formula for the orbital magnetization of interacting electrons…
We investigate possible topological superconductivity in the Kondo-Kitaev model on the honeycomb lattice, where the Kitaev spin liquid is coupled to conduction electrons via the Kondo coupling. We use the self-consistent Abrikosov-fermion…
We investigate the Stirling-cycle performance of a Heisenberg--Kitaev magnonic medium with Dzyaloshinskii--Moriya (DM) interactions. Using linear spin-wave theory, we show the DM interaction preserves spectral symmetry, yielding even…
Frustration refers to the inability to satisfy competing interactions simultaneously, often leading to a large number of degenerate ground states. This can suppress ordering tendencies, sometimes resulting in a spin liquid phase. An…
The magnetic orders in Na$_2$IrO$_3$ and $\alpha-$RuCl$_3$, honeycomb systems with strong spin-orbit coupling and correlations, have been recently described by models with the dominant Kitaev interactions. In this work we discuss how the…
The bond-disordered Kitaev model attracts much attention due to the experimental relevance in $\alpha$-RuCl$_3$ and $A_3$LiIr$_2$O$_6$ ($A=$ H, D, Ag, $\textit{etc.}$). Applying a magnetic field to break the time-reversal symmetry leads to…
The magnetic and orbital orders for the bilayer manganites in the doping region $0.5 < x <1.0$ have been investigated from a model that incorporates the two $e_g$ orbitals at each Mn site, the inter-orbital Coulomb interaction and lattice…
We study the hole-doped Kitaev-Heisenberg chain using the density-matrix renormalization group. In the Kitaev-only limit, the bond-directional exchange itself promotes pairing, favoring spin-singlet and spin-triplet superconducting…
The Kitaev model with an applied magnetic field in the $H||[111]$ direction shows two transitions: from a non-abelian gapped quantum spin liquid (QSL) to a gapless QSL at $H_{c1} \simeq 0.2K$ and a second transition at a higher field…