相关论文: Excitonic complexes in quantum Hall systems
We construct model wavefunctions for a family of single-quasielectron states supported by the $\nu=1/3$ fractional quantum Hall (FQH) fluid. The charge $e^*$ = $e/3$ quasielectron state is identified as a composite of a charge-$2e^*$…
In wide GaAs quantum wells where two electric subbands are occupied we apply a parallel magnetic field or increase the electron density to cause a crossing of the two $N=0$ Landau levels of these subbands and with opposite spins. Near the…
The single-particle spectral function for an incompressible fractional quantum Hall state in the presence of a scalar short-ranged attractive impurity potential is calculated via exact diagonalization within the spherical geometry. In…
We study the system of up to four negatively charged magneto-excitons (X-'s) in the spherical geometry, using the exact-diagonalization techniques. At low energies, X-'s are bound and behave like charged particles without internal dynamics.…
Exciton condensation, characterized by uniform phase coherence across macroscopic length scales, has enabled the discovery of a variety of excitonic states, greatly enriching our understanding of correlated many-body physics. More exotic…
Photoluminescence (PL) has been used to study two-dimensional incompressible electron liquids in high magnetic fields for nearly two decades. However, some of the observed anomalies coincident with the fractional quantum Hall effect are…
Semiconductors in all dimensionalities ranging from 0D quantum dots and molecules to 3D bulk crystals support bound electron-hole pair quasiparticles termed as excitons. Over the past two decades, the emergence of a variety of…
Using the projector-based renormalization method we investigate the formation of the excitonic insulator phase in the two-dimensional (2D) spinless Falicov-Kimball model with dispersive $f$ electrons and address the existence of excitonic…
Bound electron-hole excitonic states are generally not expected to form with charges of negative effective mass. We identify such excitons in a single layer of the semiconductor WSe2, where they give rise to narrow-band upconverted…
Quasielectrons and quasiholes in the fractional quantum Hall liquids obey fractional (including nontrivial mutual) exclusion statistics. Their statistics matrix can be determined from several possible state-counting scheme, involving…
Resonant Raman scattering in semiconductor quantum dots with spherical shape is theoretically investigated. The Frohlich-like interaction between electronic states and optical vibrations has been considered. The Raman profiles are studied…
Bilayer quantum Hall systems at \nu =1 support an excitonic ground state. In addition to the usual charged quasiparticles, this system possesses a condensate degree of freedom: exciton transport. Detection of this neutral transport mode is…
Using exact numerical techniques we investigate the nature of excitonic (electron-hole) bound states and the development of exciton coherence in the one-dimensional half-filled extended Falicov-Kimball model. The ground-state phase diagram…
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…
Despite a long history, certain aspects of excitons - the bound inter-band states which form when a valence band hole and a conduction band electron pair - have remained relatively unexplored. This holds particularly true for the…
We calculate in an analyical fashion the energies and net spins of skyrmions in fractional quantum Hall systems, based on the suggestion that skyrmion states are spontaneously $L_Z$ and $S_Z$ symmetry-breaking states. The quasihole-skyrmion…
We report calculations of oscillator strengths for the far infrared absorption of light by the excitonic complexes Xn- (the excess charge, n, ranging from one to four) confined in quantum dots. The magnetic field is varied in an interval…
Using Coulomb drag as a probe, we explore the excitonic phase transition in quantum Hall bilayers at nu=1 as a function of Zeeman energy, E_Z. The critical layer separation d/l for exciton condensation initially increases rapidly with E_Z,…
he properties of excitons formed in spherical quantum dots are studied using the $\mathbf{k}\cdot\mathbf{p}$ method within the Hartree approximation. The spherical quantum dots considered have a central core and several concentric layers of…
Exciton polaritons are hybrid particles of excitons (bound electron-hole pairs) and cavity photons, which are renowned for displaying Bose Einstein condensation and other coherent phenomena at elevated temperatures. However, their formation…