Related papers: Exciton BCS or BEC state in a semiconductor bilaye…
Superconductivity emerges from the spatial coherence of a macroscopic condensate of Cooper pairs. Increasingly strong binding and localization of electrons into these pairs compromises the condensate's phase stiffness, thereby limiting…
Coulomb bound electron-hole pairs, excitons, govern the optical properties of semi-conducting transition metal dichalcogenides like MoS$_2$ and WSe$_2$. We study optical transitions at the K-point for 2H homobilayer MoS$_2$ in Density…
Employing unbiased sign-problem-free quantum Monte Carlo, we investigate the effects of long-range Coulomb forces on BEC of bipolarons using a model of bond phonon-modulated electron hopping. In absence of long-range repulsion, this model…
The ground state of two-dimensional (2D) electron systems with equal low densities of electrons and holes in nearby layers is an exciton fluid. We show that a reservoir for excitons can be established by contacting the two layers separately…
A quasi-exciton condensate is a phase characterized by quasi-long range order of an exciton (electron-hole pair) order parameter. Such a phase can arise naturally in a system of two parallel oppositely doped quantum wires, coupled by…
A theoretical model is developed for treating super conductive Bose-Einstein condensation (BEC) effects for excitons in planar systems, under the condition that many excitons are included in a surface area, with the dimensions of the…
Excitons, Coulomb-bound electron-hole pairs, are the fundamental excitations governing the optoelectronic properties of semiconductors. While optical signatures of excitons have been studied extensively, experimental access to the excitonic…
We present a stability analysis on a driven-dissipative electron-hole condensate in the BCS (Bardeen-Cooper-Schrieffer)-BEC (Bose-Einstein-condensation)-crossover region. Extending the combined BCS-Leggett theory with the generalized random…
A microscopic theory is developed to analyze the dynamics of exciton formation out of incoherent carriers in semiconductor heterostructures. The carrier Coulomb and phonon interaction is included consistently. A cluster expansion method is…
In this work, we study some general property of a strongly correlated electron system defined on a lattice. Assuming that the lattice system exhibits off-diagonal long range order, we show rigorously that this assumption would lead to…
Excitons are electron-hole pairs appearing below the band gap in insulators and semiconductors. They are vital to photovoltaics, but are hard to obtain with time-dependent density-functional theory (TDDFT), since most standard…
We develop a consistent theory of the interlayer exciton-polaron formed in atomically-thin bilayers. Coulomb attraction between an electron and a hole situated in the different layers results in their flexural deformation and provides an…
Many-body interactions can produce novel ground states in a condensed-matter system. For example, interacting electrons and holes can spontaneously form excitons, a neutral bound state, provided that the exciton binding energy exceeds the…
The ground and first excited state of two superconducting layers in interaction are studied considering two different coupling terms, one represented by the standard Josephson interaction, and one new, which is a superexchange pairing force…
The non elementary-boson nature of excitons controls Bose-Einstein condensation in semiconductors. Composite excitons interact predominantly through Pauli exclusion; this produces dramatic couplings between bright and dark states. In…
Bilayer electron-hole systems, where carriers in one layer are electrons and carriers in the other are holes, have been actively investigated in recent years with the focus on Bose-Einstein condensation of excitons. This condensation is…
Optical bound states in the continuum (BICs) provide a way to engineer very narrow resonances in photonic crystals. The extended interaction time in such systems is particularly promising for enhancement of nonlinear optical processes and…
A theoretical study of the exciton binding energy in the two-dimensional hexagonal boron nitride monolayer is presented within the tight-binding approximation (TBA). A self-consistent equation for the interband electron-hole propagators is…
The condensation of excitons, bound electron-hole pairs in a solid, into a coherent collective electronic state was predicted over 50 years ago. Perhaps surprisingly, the phenomenon was first observed in a system consisting of two…
The correlation function of radiation from a high-quality semiconductor microcavity at the resonant laser excitation demonstrates oscillations with surprisingly long-period and damping times of a nanosecond range. It was shown that the…