相关论文: Exact quantum spin liquids with Fermi surfaces in …
Quantum spin liquids, a highly topologically entangled, dynamically correlated state where quantum fluctuations preclude any long-range ordering down to absolute zero. In the search for a topologically robust qubit, the scientific community…
The ground state of the Hubbard model with nearest-neighbor hopping on the square lattice at half filling is known to be that of an antiferromagnetic (AFM) band insulator for any on-site repulsion. At finite temperature, the absence of…
Fermionic valence bond approach in terms of SU(4) representation is proposed to describe the $J_{1}-J_{2}$ frustrated Heisenberg antiferromagnetic (AF) model on a {\it bipartite} square lattice. A uniform mean field solution without…
The quantum antiferromagnet on the pyrochlore lattice offers an archetypal frustrated system, which potentially realizes a quantum spin liquid characterized by the absence of standard spontaneous symmetry breaking even at zero temperature,…
In this paper we propose an exactly solvable model of a topological insulator defined on a spin-1/2 square decorated lattice. Itinerant fermions defined in the framework of the Haldane model interact via the Kitaev interaction with spin-1/2…
We show that gapless spin liquids, which are potential candidates to describe the ground state of frustrated Heisenberg models in two dimensions, become trivial insulators on cylindrical geometries with an even number of legs. In…
Mott insulators with a half-filled band of electrons on the triangular lattice have been recently studied in a variety of organic compounds. All of these compounds undergo transitions to metallic/superconducting states under moderate…
The frustrated spin-one-half Heisenberg model on triangualr and Kagome Lattices is mapped onto a single specis of fermion carrying statistical flux. The corresponding Chern-Simons gauge theory is analyzed at the Gaussian level and found to…
We study the emergence of altermagnetism from repulsive interactions for electrons on the Lieb lattice as a model of quasi-2D oxychalcogenides with the so-called "anti-CuO$_{2}$" lattice structure. A comprehensive study of the Lieb lattice…
An emergent $\mathrm{SU}(4)$ symmetry discovered in the microscopic model for $d^1$ honeycomb materials [M.~G.~Yamada, M.~Oshikawa, and G.~Jackeli, Phys. Rev. Lett. \textbf{121}, 097201 (2018).] has enabled us to tailor exotic…
Exotic quantum spin liquid (QSL) is formed with such hypothetic particles as fermionic spinons carrying spin 1/2 and no charge. Here we calculate its thermodynamic and relaxation properties. Our calculations unveil the fundamental…
It is widely believed that the $U(1)$ spin liquid with a large spinon Fermi surface(SFS state) can be realized in the spin-$\frac{1}{2}$ $J_{1}-J_{4}$ model on the triangular lattice, when the ring exchange coupling $J_{4}$ is sufficiently…
We present an exactly solvable spin-3/2 model defined on a pentacoordinated three-dimensional graphite lattice, which realizes a novel quantum spin liquid with second-order topology. The exact solutions are described by Majorana fermions…
We develop a theory of a hybrid state, where quasi-particles coexist with strong collective modes, taking as a starting point a model of infinitely many 1D Mott insulators coupled by a weak interchain tunneling. This state exists at an…
The periodic Anderson model is a classic theoretical model for understanding novel physics in heavy fermion systems. Here, we modify it with the Sachdev-Ye-Kitaev interaction, (random all-to-all interaction) thus the resultant model admits…
The Kitaev spin liquid provides a rare example of well-established quantum spin liquids in more than one dimension. It is obtained as the exact ground state of the Kitaev spin model with bond-dependent anisotropic interactions. The peculiar…
Motivated by recent numerical studies reporting putative quantum paramagnetic behavior in spin-$1/2$ Heisenberg models on the maple-leaf lattice, we classify Abrikosov fermion mean-field Ans\"atze of fully symmetric $U(1)$ and…
The properties of the groundstate and first excitations of 2dimensionnal quantum antiferromagnets are rapidly sketched. A special emphasis is put on the gapped phases: Valence Bond Crystals and the two types of Spin Liquids. New results on…
We consider conditions for existence of fermionic quasiparticles in a strongly anisotropic quasi-one-dimensional metal. The adopted model is a model of chains of spin-1/2 Luttinger liquid coupled by small interchain hopping. It is shown…
We study a model of hard-core bosons with short-range repulsive interactions at half-filling on the kagome lattice. Using quantum Monte Carlo (QMC) numerics, we find that this model shows a continuous superfluid to insulator quantum phase…