# Edge effect on the current-temperature characteristic of thermionic cathodes

@inproceedings{Sitek2021EdgeEO, title={Edge effect on the current-temperature characteristic of thermionic cathodes}, author={Anna Sitek and Kristinn Torfason and Andrei Manolescu and 'Ag'ust Valfells}, year={2021} }

We perform a computational study, based on the molecular dynamics method, of the shape of Miram curves obtained from microscale planar diodes. We discuss the smooth transition from the source-limited to space-charge-limited regime due to the finite size of the emitter, i.e. the ”knee” in the Miram curve. In our model we find that the smoothing occurs mostly due to the increased emission at the external edges of the emitting area, and that the knee becomes softer when the size of the emitting…

## References

SHOWING 1-10 OF 23 REFERENCES

### Effect of Nonuniform Emission on Miram Curves

- PhysicsIEEE Transactions on Plasma Science
- 2020

Analysis of temperature-limited flow, space-charge-limited flow, and the transition between them using a simple planar diode with a thermionic cathode, in which the cathode surface has spatially…

### Analysis of Anode Current From a Thermionic Cathode With a 2-D Work Function Distribution

- PhysicsIEEE Transactions on Plasma Science
- 2021

A model of a thermionic cathode in a planar diode in which the Poisson and Vlasov equations are solved in 3-D assuming an infinite magnetic field is presented. We explore how 2-D work function…

### Space-Charge Effects in the Field-Assisted Thermionic Emission from Nonuniform Cathodes

- Physics
- 2020

We show how space-charge affects thermionic emission from cathodes with two different values of work function that form a checkerboard pattern of finite extent on the cathode surface. We confirm…

### Space-Charge Limited Current From a Finite Emitter in Nano- and Microdiodes

- PhysicsIEEE Transactions on Electron Devices
- 2021

We simulate numerically the classical charge dynamics in a microscopic, planar, vacuum diode with a finite emitter area and a finite number of electrons in the gap. We assume that electrons are…

### Two-dimensional space-charge-limited emission: beam-edge characteristics and applications.

- PhysicsPhysical review letters
- 2001

The characteristics of planar diode electron emission in 2D space with the emphasis on the transition region between the beam and vacuum are investigated and increased current density "wings" are observed near the beam edges in a 2D finite element, electrostatic ray-tracing code.

### Physics of thermionic dispenser cathode aging

- Physics
- 2003

A dispenser cathode life model (DCLM) was originally published in 1984. More recent life test data have substantiated the basic physics used in the DCLM. However, re-evaluation of the model with this…

### Correlation Between Emission Behavior and Surface Features of Scandate Cathodes

- PhysicsIEEE Transactions on Electron Devices
- 2009

Special emission behaviors have been observed historically and recently on scandate cathodes. For a better understanding of the phenomena, we investigated the correlation between emission properties…

### Emission Characteristics of Nanosized Scandia-Doped Dispenser Cathodes in Open Electron-Gun Structures

- PhysicsIEEE Transactions on Electron Devices
- 2011

The emission properties of nanosized scandia-doped dispenser cathodes tested in open-structure Pierce electron guns are reported in this paper. Over 100 A/cm<sup>2</sup> and over 80 A/cm<sup>2</sup>…

### Emission spread in thermionic cathodes

- Environmental ScienceFifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786)
- 2004

Summary form only given. Emission spread is the deviation of measured emission current from values calculated using the Richardson-Dushmann emission equation with a single best-fit effective work…

### Evaluation and Influence of Gyrotron Cathode Emission Inhomogeneity

- PhysicsIEEE Transactions on Electron Devices
- 2017

In order to evaluate the emission inhomogeneity of thermionic gyrotron cathode emitters, a novel definition of emission inhomogeneity and evaluating method from the current–voltage characteristics is…