相关论文: A Time Domain Coupled Electronic-Optical Simulatio…
Photoluminescence measurements on high-quality InGaN quantum wells reveal that carriers diffuse laterally to long distances at room temperature, up to tens of microns. This behavior, which shows a pronounced dependence on the excitation…
Temporally and spectrally resolved dynamics of optically excited carriers in graphene has been intensively studied theoretically and experimentally, whereas carrier diffusion in space has attracted much less attention. Understanding the…
Owing to their exceptional semiconducting properties, hybrid inorganic-organic perovskites show great promise as photovoltaic absorbers. In these materials, long-range diffusion of charge carriers allows for most of the photogenerated…
The Debye-Falkenhagen differential equation is commonly used as a mean-field macroscopic model for describing electrochemical ionic drift and diffusion in dilute binary electrolytes when subjected to a suddenly applied potential smaller…
We present a computationally tractable scheme of time-dependent transport phenomena within open-boundary time-dependent density-functional-theory. Within this approach all the response properties of a system are determined from the…
We propose a hybridizable discontinuous Galerkin (HDG) finite element method to approximate the solution of the time dependent drift-diffusion problem. This system involves a nonlinear convection diffusion equation for the electron…
The photoluminescence in amorphous semiconductors decays according to power law $t^{-delta}$ at long times. The photoluminescence is controlled by dispersive transport of electrons. The latter is usually characterized by the power $alpha$…
The diffusion of electron-hole pairs, which are excited in an intrinsic graphene by the ultrashort focused laser pulse in mid-IR or visible spectral region, is described for the cases of peak-like or spread over the passive region…
The determination of the carrier diffusion length of semiconductors such as GaN and GaAs by cathodoluminescence imaging requires accurate knowledge about the spatial distribution of generated carriers. To obtain the lateral distribution of…
Light emitting diodes (LEDs) based on Gallium Nitride (GaN) have been revolutionizing various applications in lighting, displays, medical equipment, and other fields. However, their energy efficiency is still below expectations in many…
We investigate, both theoretically and experimentally, the drift, diffusion, and recombination of excitons in the strain field of an edge threading dislocation intersecting the GaN{0001} surface. We calculate and measure hyperspectral…
We review the description and modeling of transport phenomena among the electron systems coupled via scalar or vector photons. It consists of three parts. The first part is about scalar photons, i.e., Coulomb interactions. The second part…
A typical graphene heterojunction device can be divided into two classical zones, where the transport is basically diffusive, separated by a "quantum active region" (e.g., a locally gated region), where the charge carriers are scattered…
We study carrier transport, distribution, and recombination in dual-color c-plane InGaN/GaN LEDs using spectral analysis and small-signal electroluminescence (SSEL). The emissions from green and blue quantum wells (QWs) were experimentally…
The transport of charged particles in various astrophysical environments permeated by magnetic fields is described in terms of a diffusion process, which relies on diffusion-tensor parameters generally inferred from Monte-Carlo simulations.…
We study charge transport in a graphene zigzag nanoribbon driven by an external time-periodic kicking potential. Using the exact solution of the time-dependent Dirac equation with a delta-kick potential acting in each period, we study the…
In this paper the Boltzmann equation describing the carrier transport in a semiconductor is considered. A modified Chapman-Enskog method is used, in order to find approximate solutions in the weakly non-homogeneous case. These solutions…
We present an optical spectroscopy study of non-polar GaN/AlN quantum dots by time-resolved photoluminescence and by microphotoluminescence. Isolated quantum dots exhibit sharp emission lines, with linewidths in the 0.5-2 meV range due to…
The nonlinear boson diffusion equation is taken as a basis to account for the fast thermalization of gluons in the initial stages of relativistic heavy-ion collisions. For constant drift and diffusion coefficients with schematic initial…
We report on the exciton propagation in polar (Al,Ga)N/GaN quantum wells over several micrometers and up to room temperature. The key ingredient to achieve this result is the crystalline quality of GaN quantum wells (QWs) grown on GaN…