Related papers: Enhanced space charge limited current for curved e…
Field emission studies incorporating the effect of space charge reveal that for planar emitters, the steady-state field $E_P$, after initial transients, settles down to a value lower than the vacuum field $E_L$. The ratio $\vartheta =…
We investigate the dynamics of a space-charge limited, photoinjected, electron beam in a microscopic vacuum diode. Due to the small nature of the system it is possible to conduct high-resolution simulations where the number of simulated…
Numerical solutions to the 1D steady-state Vlasov-Poisson system are used to develop a straightforward empirical formula for the electric current density transmitted through a vacuum diode (voltage gap) as a function of gap distance, gap…
For field emission (FE), it is widely expected that its emitting current density $J$ will become space-charge-limited current (SCLC) due the built-up of charge in-transit within a gap spacing $D$ biased at sufficiently large voltage $V$. In…
A drastic cumulation of current density caused by electrostatic repulsion in relativistic vacuum diodes with ring-type cathodes is described theoretically and confirmed experimentally. The distinctive feature of the suggested cumulation…
In this paper we analyze the motion of charged particles in a vacuum tube diode by solving linear differential equations. Our analysis is based on expressing the volume charge density as a function of the current density and coordinates…
A one-dimensional (1D) model has been constructed to study the transition of the time-dependent ultrafast laser photo-electron emission from a flat metallic surface to the space charge limited (SCL) current, including the effect of…
Recent studies have applied variational calculus, conformal mapping, and point transformations to generalize the one-dimensional (1D) space-charge limited current density (SCLCD) and electron emission mechanisms to nonplanar geometries;…
Simulations have shown that space-charge effects can lead to regular modulation of photoemitted beams in vacuum diodes with gap sizes on the order of 1 micron and accelerating voltage on the order of 1V. These modulations are in the THz…
Diodes used in most high power devices are inherently open. It is shown that under such circumstances, there is a loss of electromagnetic radiation leading to a lower critical current as compared to closed diodes. The power loss can be…
Using a combination of Eulerian and Lagrangian variables we obtain some exact results and good approximation schemes for the time evolution of the electron flow from a no-current state to a final stationary current state in a planar…
We use computational simulations to study the electron emission and propagation in planar vacuum diodes. We show how space-charge affects thermionic emission from cathodes with two different values of work function that form a checkerboard…
We present results demonstrating the space charge-mediated transition between classical, diffusion-limited current and surface-conduction dominant over-limiting current in a shallow micro-nanochannel device. The extended space charge layer…
It has been empirically observed in both experiments and particle-in-cell simulations that space-charge-dominated beams suffer strong growth in statistical phase-space area (degraded quality) and particle losses in alternating gradient…
While space-charge-limited current measurements are often used to characterize charge-transport in relatively intrinsic, low-mobility semiconductors, it is currently difficult to characterize lightly or heavily doped semiconductors with…
The maximum current that could be carried in a vacuum tube is given by the so-called Child Langmuir law. A scheme where this limit could be overcome via the pondermotive potential is proposed. The estimation shows that the limit could be…
(abbrev.) Linear acceleration emission occurs when a charged particle is accelerated parallel to its velocity. We evaluate the spectral and angular distribution of this radiation for several special cases, including constant acceleration…
In this Letter we research the space charge limiting current value at which the oscillating virtual cathode is formed in the relativistic electron beam as a function of the external magnetic field guiding the beam electrons. It is shown…
We investigate the subtle effects of diffuse charge on interfacial kinetics by solving the governing equations for ion transport (Nernst-Planck) with realistic boundary conditions representing reaction kinetics (Butler-Volmer) and…
The distribution of electric current on an electrode surface in electrolyte varies with time due to charge accumulation at a capacitive interface, as well as due to electrode kinetics and concentration polarization in the medium. Initially,…