相关论文: Composite excitonic states in doped semiconductors
The electronic and optical properties of the paradigmatic F4TCNQ-doped pentacene in the low-doping limit are investigated by a combination of state-of-the-art many-body \emph{ab initio} methods accounting for environmental screening…
Confined excitonic complexes in two dimensions, consisting of N_e electrons and N_h holes, are studied by means of Bethe-Goldstone equations. Systems with up to twelve pairs, and asymmetric configurations with N_e \ne N_h are considered.…
We consider the excitonic correlations in the two band solid state system composed of the valence band and conduction band electrons. We treat the phase coherence mechanism in the system by presenting the electron operator as a fermion…
We derive a model for the highest occupied molecular orbital band of a C60 crystal which includes on-site electron-electron interactions. The form of the interactions are based on the icosahedral symmetry of the C60 molecule together with a…
We present a Hamiltonian in real space which is well suited to study numerically the behavior of holes introduced in III-V semiconductors by Mn doping when the III$^{3+}$ ion is replaced by Mn$^{2+}$. We consider the actual lattice with the…
Electrons and holes can spontaneously form excitons and condense in a semimetal or semiconductor, as predicted decades ago. This type of Bose condensation can happen at much higher temperatures in comparison with dilute atomic gases.…
From recent Hall effect measurements and angle-resolved photo-emission spectroscopy the interesting picture emerges of co-existing hole- and electron-like quasiparticle bands, both in electron- and hole-doped superconducting cuprates. We…
Electron-hole bound pairs, or excitons, are common excitations in semiconductors. They can spontaneously form and ``condense'' into a new insulating ground state -- the so-called excitonic insulator -- when the energy of electron-hole…
Photo-doping of Mott insulators or correlated metals can create an unusual metallic state which simultaneously hosts hole-like and electron-like particles. We study the dynamics of this state up to long times, as it passes its kinetic…
An ab initio approach is presented for studying the collective excitations in excitonic insulators, charge/spin density waves and superconductors. We derive the Bethe-Salpeter-Equation for the particle-hole excitations in the quasiparticle…
Excitons are electron-hole (e-h) pair quasiparticles, which may form a Bose-Einstein condensate (BEC) and collapse into the phase coherent state at low temperature. However, because of ephemeral strength of pairing, a clear evidence for BEC…
We investigate the pairing state in a doped band insulator under a periodic driving field. We employ a correlated fermionic model on a honeycomb lattice, in which pairing glue is obtainable via repulsive interactions, and derive an…
The optical spectra of two dimensional (2D) materials exhibit sharp absorption peaks that are commonly identified with exciton and trions (or charged excitons). In this paper, we show that excitons and trions in doped 2D materials can be…
Floquet engineering of electronic states by light is a central topic in modern experiments. However, the impact of many-body interactions on the single-electron properties remains unclear in this non-equilibrium situation. We propose that…
A family of models is proposed to describe the motion of holes in a fluctuating quantum dimer background on the square lattice. Following Castelnovo et al. [Ann. Phys. (NY) 318, 316 (2005)], a generalized Rokhsar-Kivelson Hamiltonian at…
We introduce the notion of superstructure Mottness to describe the Mott and Wigner-Mott transition in doped strongly correlated electron systems at commensurate filling fractions away from one electron per site. We show that superstructure…
Excitons in thin layers of semiconducting transition metal dichalcogenides are highly subject to the strongly modified Coulomb electron-hole interaction in these materials. Therefore, they do not follow the model system of a two-dimensional…
Systems of up to twelve electrons and six holes on the Haldane sphere are studied by exact numerical diagonalization. The low lying states of the system involve bound excitonic complexes such as (X^n)-. The angular momenta of these…
We study the electron-hole pair (or excitonic) condensation in the extended Falicov-Kimball model at finite temperatures based on the cluster mean-field-theory approach, where we make the grand canonical exact-diagonalization analysis of…
We explore the phase diagram of a twisted bilayer of strongly interacting electrons on a honeycomb lattice close to half-filling using the slave boson mean-field theory. Our analysis indicates that a variety of new phases can be realized as…