Related papers: Bandgap renormalization of modulation doped quantu…
We calculate the electronic structure for a modulation doped and gated T-shaped quantum wire using density functional theory. We calculate the bandgap renormalization as a function of the density of conduction band electrons, induced by the…
In this paper we consider two different geometry of quasi one-dimensional semiconductors and calculate their exchange-correlation induced bandgap renormalization (BGR) as a function of the electron-hole plasma density and quantum wire…
We investigate the dynamical self-energy corrections of the electron-hole plasma due to electron-electron and electron-phonon interactions at the band edges of a quasi-one dimensional (1D) photoexcited electron-hole plasma. The…
The photoluminescence (PL) spectra of a two-dimensional electron system induced in a Be-delta-doped GaAs/AlGaAs quantum well (QW) with a back gate are measured. The electron density is controlled from 1 X 10^{9} cm^{-2} to 2.5 X 10^{11}…
Screening due to surrounding dielectric medium reshapes the electron-hole interaction potential and plays a pivotal role in deciding the binding energies of strongly bound exciton complexes in quantum confined monolayers of transition metal…
Bandgap control is of central importance for semiconductor technologies. The traditional means of control is to dope the lattice chemically, electrically or optically with charge carriers. Here, we demonstrate for the first time a widely…
Interband absorption and luminescence of quasi-two-dimensional, circularly symmetric, N_e electron quantum dots are studied at high magnetic fields, 8<B<60 T, and low temperatures, T<<2 K. In the N_e=0 and 1 dots, the initial and final…
We consider theoretically the formation and stability of quasi-one dimensional many-body excitons in GaAs quantum wire structures under external photoexcitation conditions by solving the dynamically screened Bethe-Salpeter equation for…
A key feature of monolayer semiconductors, such as transition-metal dichalcogenides, is the poorly screened Coulomb potential, which leads to large exciton binding energy (Eb) and strong renormalization of the quasiparticle bandgap (Eg) by…
We measured polarization-dependent photoluminescence-excitation spectra of highly uniform T-shaped quantum wires at 5 K. We attribute one peak to the 1D-exciton ground state and the continuous absorption band to 1D continuum states. These…
In spite of a large quantity of papers devoted to the mangetoluminescence from CdTe/(Cd,Mg)Te, quantum wells there have been no attempts to analyze it on the basis of the band-structure calculations. This has been proposed in the present…
Voltage modulated electroluminescence spectra and low frequency ({\leq} 100 kHz) impedance characteristics of electroluminescent diodes are studied. Voltage modulated light emission tracks the onset of observed negative capacitance at a…
In this paper, we investigate renormalization of charge carrier effective masses and bandgap narrowing in n-GaAs and wurtzite-type n-GaN over a wide range of temperatures and dopant concentrations. The calculations are based on the Green's…
In contrast to interband excitons in undoped quantum wells, doped quantum wells do not display sharp resonances due to excitonic bound states. In these systems the effective Coulomb interaction between electrons and holes typically only…
An optical method is suggested to determine the concentration of two-dimensional electrons in modulation-doped quantum wells at low and moderate electron densities between 10^{9} and 2x10^{11} cm^{-2}. The method is based on an analysis of…
This work presents epitaxial growth and optical spectroscopy of CdTe quantum dots (QDs) in (Cd,Zn,Mg)Te barriers placed on the top of (Cd,Zn,Mg)Te distributed Bragg reflector. The formed photonic mode in our half-cavity structure permits to…
We study the excitonic structure of CdSe/ZnSe self assembled quantum dots (SAQD) by magneto-photoluminescence (PL) spectroscopy. Using fixed 200 nm apertures through a metal film, we are able to probe single narrow (200 micro-eV)…
Two-dimensional (2D) transition metal dichalcogenides (TMDs) exhibit novel electrical and optical properties and are emerging as a new platform for exploring 2D semiconductor physics. Reduced screening in 2D results in dramatically enhanced…
The electronic band gap of a two-dimensional semiconductor within a device architecture is sensitive to variations in screening properties of adjacent materials in the device and to gate-controlled doping. Here, we employ micro-focused…
We present a study of the photoluminescence (PL) properties of heavily Be delta-doped GaAs/AlAs multiple quantum wells measured at room and liquid nitrogen temperatures. Possible mechanisms for photocarriers recombination are discussed,…