Related papers: Topological spin ordering via Chern-Simons superco…
We propose that non-collinear magnetic order in quantum magnets can harbor a novel higher-order topological magnon phase with non-Hermitian topology and hinge magnon modes. We consider a three-dimensional system of interacting local moments…
Motivated by recent experimental breakthroughs, we propose a strategy to design two-dimensional spin lattices with competing interactions that lead to non-trivial emergent quantum states. We consider $S=1/2$ nanographenes with $C_3$…
By analytically solving the Bogoliubov-de Gennes equations we study the fermion bound states at the center of the core of a vortex in a two-dimensional superconductor. We consider three kinds of 2D superconducting models: (a) a standard…
We study ordered states and topological excitations in a quasi-two-dimensional magnet, modeled by a square lattice with spins $s {=} 1$ at all sites, and the Hamiltonian with biquadratic exchange interaction between nearest neighbor sites.…
Motivated by the strong-correlation phenomenology observed near the superconducting phase in twisted bilayer WSe$_2$, we study multi-orbital $t$-$J$ models that are derived from different parameter regimes. The models contain effective…
We consider the SU(2) gauge theory for spin fluctuations in the two-dimensional Hubbard model, where the electron field is fractionalized in terms of spinons and chargons. In this theory, spinons are described by a non-linear sigma model,…
We introduce exactly solvable models of interacting (Majorana) fermions in $d \ge 3$ spatial dimensions that realize a new kind of topological quantum order, building on a model presented in ref. [1]. These models have extensive topological…
We demonstrate that ultracold polyatomic symmetric top molecules, such as methyl fluoride, loaded into an optical lattice and subject to DC electric and microwave field dressing, can display topological order via a self-consistent analog of…
We propose and analyse an efficient scheme for simulating higher-order topological phases of matter in two dimensional (2D) spin-phononic crystal networks. We show that, through a specially designed periodic driving, one can selectively…
The concepts of Weyl fermions and topological semimetals emerging in three-dimensional momentum space are extensively explored owing to the vast variety of exotic properties that they give rise to. On the other hand, very little is known…
We propose a minimal interacting lattice model for two-dimensional class-$D$ higher-order topological superconductors with no free-fermion counterpart. A Lieb-Schultz-Mattis-type constraint is proposed and applied to guide our lattice model…
Magnetic multiple-$Q$ states consisting of multiple spin density waves are a source of unconventional topological spin textures, such as skyrmion and hedgehog. We theoretically investigate a topologically nontrivial double-$Q$ state with a…
We discuss an extension of higher order topological phases to include bosonic systems. We present two spin models for a second-order topological phase protected by a global $\mathbb{Z}_2\times\mathbb{Z}_2$ symmetry. One model is built from…
We construct microscopic Hamiltonians for symmetry-preserving topologically ordered states on the surface of topological crystalline superconductors, protected by a $\mathbb{Z}_2$ reflection symmetry. Starting from $\nu$ Majorana cones on…
A unitary transformation is applied to the Hubbard model, which maps the Hubbard interaction to a single particle term. The resulting Hamiltonian consists of unconstrained fermions, which is then mapped to a Hamiltonian of spinless fermions…
Chiral topological orders formed in correlated fermion systems have been widely explored. However, the mechanism on how they emerge from interacting fermions is still unclear. Here, we propose a susceptibility condition. Under this…
Antiferromagnetic and ferro/ferrimagnetic orders are typically exclusive in nature, thus, their co-existence in atomic-scale proximity is expected only in heterostructures. Breaking this paradigm and broadening the range of unconventional…
Many physical properties of high-temperature (high-Tc) superconductors are two-dimensional phenomena derived from their square planar CuO2 building blocks. This is especially true of the magnetism from the copper ions. As mobile charge…
Fermi liquid theory provides a remarkably powerful framework for the description of the conduction electrons in metals and their ordering phenomena, such as superconductivity, ferromagnetism, and spin- and charge-density-wave order. A…
A model is introduced describing the interplay between superconductivity and spin-ordering. It is characterized by on-site repulsive electron-electron interactions, causing antiferromagnetism, and nearest-neighbor attractive interactions,…