相关论文: Theory of multiexciton generation in semiconductor…
We study the coherent mixing between two-particle (single exciton) and four-particle (biexciton) states of a semiconductor nanocrystal resulting from the coulomb coupling between states with different numbers of electron-hole pairs. Using a…
We study the role of the effective mass, band mixing and phonon emission on multiexciton generation in IV-VI nanocrystals. A 4-band k dot p effective mass model, which allows for an independent variation of these parameters, is adopted to…
Multiple exciton generation (MEG) is a process in which more than one exciton is generated upon the absorption of a high energy photon, typically higher than two times the band gap, in semiconductor nanocrystals. It can be observed…
Excitonic contributions to absorption and photocurrent generation in semiconductor nanostructures are described theoretically and simulated numerically using steady-state non-equilibrium Green's function theory. In a first approach, the…
We study the exciton dynamics in an optically excited nanocrystal quantum dot. Multiple exciton formation is more efficient in nanocrystal quantum dots compared to bulk semiconductors due to enhanced Coulomb interactions and the absence of…
Electroluminescence (EL) of colloidal nanocrystals promises a new generation of high-performance and solution-processable light-emitting diodes (LEDs). The operation of nanocrystal-based LEDs relies on the recombination of…
Electron-phonon and exciton-phonon interactions in nanoclusters are formulated and computed under the framework of GW-BSE (Bethe-Salpeter equation) approach. The phonon effect is modeled with the two-particle representation for the first…
We study how shape affects multiexciton generation (MEG) rates in a semiconducting nanocrystal by considering CdSe nanorods with varying diameters and aspect ratios. The calculations employ an atomistic semiempirical pseudopotential model…
The statistical theory of multiple exciton generation in quantum dots which is based on the Fermi approach to the problem of multiple particle in nucleon-nucleon collisions is presented. Our estimates of the multiple exciton generation…
The electrons and excitons multiple exciton generation dynamics in two silicon clusters, or more specifically the inelastic scattering rates of electronic and excitonic states in the two silicon clusters, Si26 and Si46, are calculated using…
The effect of carrier multiplication (CM) in semiconductor nanocrystals is systematically treated by employing an exciton scattering approach. Using projection operators, we reduce the Coulomb coupled multi-exciton dynamics to scattering…
Energy-time entangled photons provide new opportunities for controlling multiphoton absorption beyond classical limits. Here, we investigate biexciton generation in nanocrystal quantum dots driven by energy-time-entangled quantum light…
We have shown theoretically that efficient multiple exciton generation (MEG) by a single photon can be observed in small nanocrystals (NCs). Our quantum simulations that include hundreds of thousands of exciton and multi-exciton states…
Multiple exciton generation (MEG) in nanometer-sized hydrogen-passivated silicon nanowires (NWs), and quasi two-dimensional nanofilms strongly depends on the degree of the core structural disorder as shown by the many-body perturbation…
We develop a quantum mechanical theory to describe the optical response of semiconductor nanostructures with a particular emphasis on higher-order harmonic Generation. Based on a tight-binding approach we take all two-particle correlations…
We show that bi-exciton formation can be highly efficient in a solar cell with the semiconductor absorber filled with an array of metallic nanoparticles having plasmonic resonance tuned to the semiconductor gap energy. This process can be…
The distribution of rates of carrier multiplication (CM) following photon absorption is calculated for semiconductor nanocrystals (NCs). The NC electronic structure is described using a screened pseudopotential method known to give reliable…
The population dynamics of single- and bi-exciton states in semiconductor nanocrystals is modeled numerically in the presence of Coulomb coupling between single- and two-exciton states and a dissipation channel in order to study the…
We use Boltzmann transport equation (BE) to study time evolution of a photo-excited state in a nanoparticle including phonon-mediated exciton relaxation and the multiple exciton generation (MEG) processes, such as exciton-to-biexciton…
We propose a novel mechanism for photogeneration of multiexcitons by single photons (carrier multiplication) in semiconductor nanocrystals. In this mechanism, the Coulomb interaction between two valence-band electrons involving their…