相关论文: Flat-band excitonic states in Kagome lattice on se…
The excitonic insulator (EI) state is a strongly correlated many-body ground state, arising from an instability in the band structure towards exciton formation. We show that the flat valence and conduction bands of a semiconducting diatomic…
The interplay between local and itinerant electrons underpins many correlated and topological quantum states. Kagome lattices provide an ideal platform by hosting both flat (localized states) and dispersive bands (itinerant states), yet…
This theoretical paper offers an explicit expression for the binding energy of excitons in a two-dimensional semiconductor with a flat valence band. The formula has been derived quasiclassically assuming that the exciton is tightly bound;…
Electron-hole pair excitations in semiconductors have been predicted to be able to give rise to a highly correlated many-body ground state, the excitonic insulator (EI). Under appropriate conditions below a critical temperature (Tc),…
We have studied how a generic bilayer kagome lattice behave upon layer rotation. We employed a Tight Binding model with one orbital per site and found (i) for low rotational angles, and at low energies, the same flat bands structure like in…
Kagome lattices supporting Dirac cone and flatband dispersions are well known as a highly frustrated, two-dimensional lattice system. Particularly the flatbands therein are attracting continuous interest based on their link to topological…
Interaction in a flat band is magnified due to the divergence in the density of states, which gives rise to a variety of many-body phenomena such as ferromagnetism and Wigner crystallization. Until now, however, most studies of the flat…
We present detailed calculations for several significant properties of the kagome lattice. We employ the Floquet-Magnus perturbation expansion to obtain the energy bands and the corresponding wave functions near the Dirac points for the…
The scaling of exciton binding energy in semiconductor quantum wires is investigated theoretically through a non-variational, fully three-dimensional approach for a wide set of realistic state-of-the-art structures. We find that in the…
Destructive interference between electron wavefunctions on the two-dimensional (2D) kagome lattice induces an electronic flat band, which could host a variety of interesting many-body quantum states. Key to realize these proposals is to…
Flat band materials such as the kagome metals or moir\'e superlattice systems are of intense current interest. Flat bands can result from the electron motion on numerous (special) lattices and usually exhibit topological properties. Their…
The energy dispersion of fermions or bosons vanishes in momentum space if destructive quantum interference occurs in a frustrated Kagome lattice with only nearest-neighbour (NN) hopping. A discrete flat band (FB) without any dispersion is…
In condensed matter physics, the Kagome lattice and its inherent flat bands have attracted considerable attention for their potential to host a variety of exotic physical phenomena. Despite extensive efforts to fabricate thin films of…
Flat electronic bands strongly enhance Coulomb interactions and can stabilize unconventional insulating states. Motivated by the recent discovery of flat bands in breathing Kagome lattices, we use first-principles GW--Bethe--Salpeter theory…
Motivated by recent advances in the realization of complex two-dimensional optical lattices, we investigate theoretically the quantum transport of ultracold fermions in an optical kagome lattice. In particular, we focus on its extensively…
Materials with kagome lattice have attracted significant research attention due to their nontrivial features in energy bands. In this work, we theoretically investigate the evolution of electronic band structures of kagome lattice in…
In the quest for topology- and correlation-driven quantum states, kagome lattice materials have garnered significant interest for their band structures, featuring flat bands (FBs) from the quantum destructive interference of the electronic…
Flat bands, characterized by zero group velocity and strong energy localization, enable interaction-enhanced phenomena across both quantum and classical systems. Existing photonic flat-band implementations were limited to evanescent-wave…
We study characteristic band structures of the fermions on a square kagome lattice, one of the two-dimensional lattices hosting a corner-sharing network of triangles. We show that the band structures of the nearest-neighbor tight-binding…
We discuss the excitons in flat band systems. Quantum metric plays a central role in determining the properties of single exciton excitation as well as the exciton condensate. While the electrons and holes are extremely heavy in flat bands,…