相关论文: Electron cascades and secondary electron emission …
Electron irradiation is essential for materials characterization and modification, though the fundamental interactions between incident electrons and host materials remain under investigation. Here, we employ first-principles simulations to…
We theoretically investigate the three-dimensional (3D) electron dynamics of graphene in real space under strong laser fields using time-dependent density functional theory (TDDFT). We successfully reproduce the reversal of current…
Graphene is expected to be rather insensitive to ionizing particle radiation. We demonstrate that single layers of exfoliated graphene sustain significant damage from irradiation with slow highly charged ions. We have investigated the ion…
The real-time electronic dynamics on material surfaces is critically important to a variety of applications. However, their simulations have remained challenging for conventional methods such as the time-dependent density-functional theory…
Characteristic properties of secondary electrons emitted from irradiated two-dimensional materials arise from multi-length and time-scale relaxation processes that connect the initial non-equilibrium excited electron distribution with their…
Using a scanning electron microscope, we observed a reproducible, discrete distribution of secondary electron intensity stemming from an atomically thick graphene film on a thick insulating substrate. The discrete distribution made it…
A thorough understanding of the electronic structure is a necessary first step for the design of nanoelectronics, chemical/bio-sensors, electrocatalysts, and nanoplasmonics using graphene. As such, theoretical spectroscopic techniques to…
The interaction of energetic ions with the electronic and ionic system of target materials is an interesting but challenging multi-scale problem and understanding of the early stages after impact of heavy, initially charged ions is…
Many of the proposed future applications of graphene require the controlled introduction of defects into its perfect lattice. Energetic ions provide one way of achieving this challenging goal. Single heavy ions with kinetic energies in the…
Graphene-based electric power generation that converts mechanical energy of flow of ionic droplets over the device surface into electricity has emerged as promising candidate for a blue-energy network. Yet the lack of a microscopic…
The plasma-material interactions present in multiple fusion and propulsion concepts between the flow of plasma through a channel and a material wall drive the emission of secondary electrons. This emission is capable of altering the…
The structure of the double-layer formed at the surface of carbon electrodes is governed by the interactions between the electrode and the electrolyte species. However, carbon is notoriously difficult to simulate accurately, even with…
The structure of the electrical double layer (EDL) formed near graphene in aqueous environments strongly impacts its performance for a plethora of applications, including capacitive deionization. In particular, adsorption and organization…
In this work, high field carrier transport in two dimensional (2D) graphene is investigated. Analytical models are applied to estimate the saturation currents in graphene, based on the high scattering rate of optical phonon emission.…
Graphene is a novel two-dimensional material with fascinating electrodynamic properties like the ability to support collective electron oscillations (plasmons) accompanied by tight confinement of electromagnetic fields. Our goal is to…
Secondary electron cascades are responsible for significant ionizations in macroscopic samples during irradiation with X-rays. A quantitative analysis of these cascades is needed, e.g. for assessing damage in optical components at X-ray…
Thermoelectric phenomena in photoexcited graphene have been the topic of several theoretical and experimental studies because of their potential usefulness in optoelectronic applications. However, available theoretical descriptions of the…
We examine the fate of fast electrons (with energies E>10 eV) in a thermal gas of primordial composition. To follow their interactions with the background gas, we construct a Monte Carlo model that includes: (1) electron-electron scattering…
The form of a sheath near a small electrode, with bias changing from below to above the plasma potential is studied using 2D particle-in-cell (PIC) simulations. Five cases are studied: (A) an electrode biased more than the electron…
Time-dependent density-functional theory simulations are performed to examine the effects of varying incident points and kinetic energies of hydrogen atom projectiles on a graphene-like structure. The simulations reveal that the incident…