Related papers: Nonlinear optical response and spin-charge separat…
Spin-charge separation is known to be broken in many physically interesting one-dimensional (1D) and quasi-1D systems with spin-orbit interaction because of which spin and charge degrees of freedom are mixed in collective excitations. Mixed…
Charge excitations in Mott insulators (MIs) are distinct from their band-insulator counterparts and they can provide a mechanism for energy harvesting in solar cells based on strongly correlated electronic materials. In this paper, we study…
We propose an effective model called the "charge model", for the half-filled one-dimensional Hubbard and extended Hubbard models. In this model, spin-charge separation, which has been justified from an infinite on-site repulsion ($U$) in…
Pump-probe response of the spin-orbit coupled Mott insulator Sr$_2$IrO$_4$ reveals a rapid creation of low energy optical weight and suppression of three dimensional magnetic order on laser pumping. Post pump there is a quick reduction of…
We study spin and charge dynamics of stripes in doped Mott insulators by considering a two-dimensional Hubbard model with N fermion flavors. For N =2 we recover the normal one-band model while for N -> infty a spin density wave mean-field…
We study theoretically the distributions of charge and spin polarization of a topological insulator ribbon, with a realistic rectangular cross section. Due to constriction in two lateral directions, the surface states discretize into a…
I discuss origin and possible experimental manifestations of charge-spin separation in 1D Luttinger and Luther-Emery liquids, the latter describing 1D Mott and Peierls insulators and superconductors. Emphasis is on photoemission where the…
As an elementary particle the electron carries spin \hbar/2 and charge e. When binding to the atomic nucleus it also acquires an angular momentum quantum number corresponding to the quantized atomic orbital it occupies (e.g., s, p or d).…
The physical nature of doped Mott-insulator has been intensively studied for more than three decades. It is well known that the single band Hubbard model or $t$-$J$ model on the bipartite lattice is the simplest model to describe a doped…
Despite fundamentally challenging in integrated (nano)photonics, achieving chip-based light nonreciprocity becomes increasingly urgent in signal processing and optical communications. Because of material incompatibilities in conventional…
We examine the third-order non-linear optical response of a one-dimensional Mott insulator coupled with phonons. The Mott insulator is described by an extended Hubbard-Holstein model. The third harmonic generation (THG) of the model is…
We use an exact holon and spinon Landau-liquid functional which describes the holon - spinon interactions at all scattering orders, to study correlation functions of integrable multicomponent many-particle problems showing both linear and…
Using dynamical mean-field theory and the non-crossing approximation as impurity solver, we study the response of a Mott insulator to strong dc electric fields. The breakdown of the Mott insulating state is triggered by field-induced…
We consider spin correlations in the one dimensional half filled repulsive Hubbard model. For very large values of the on-site repulsion U the spin correlations are dominated by virtual hopping processes of electrons and are described in…
We study the problem of one-dimensional (1D) Luttinger liquids in the insulating Mott-Hubbard phase in the presence of acoustic phonons in the semiclassical limit. We show that solitonic excitations can propagate freely in the system and…
We present a general scheme for the computation of the time dependent (TD) quadratic susceptibility ($\chi^{(2)}$) of an extended insulator obtained by applying the `$2n+1$' theorem to the action functional as defined in TD density…
Clusters of single spins form the relevant spin entities in the formation of long-range magnetic order in spin cluster Mott insulators. Such type of spin order bears resemblance to molecular crystals, and we therefore may expect a…
We study the low-energy collective properties of a 1D spin-1 Bose gas using bosonization. After giving an overview of the technique, emphasizing the physical aspects, we apply it to the $S=1$ Bose-Hubbard Hamiltonian and find a novel…
We report a resonant inelastic x-ray scattering study of charge excitations in the quasi-one-dimensional Mott insulator SrCuO2. We observe a continuum of low-energy excitations, in which a highly dispersive feature with a large sinusoidal…
Motivated by the rich interplay among electronic correlation, spin-orbit coupling (SOC), crystal-field splitting, and geometric frustrations in the honeycomb-like lattice, we systematically investigated the electronic and magnetic…