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arXiv · 0811.0334

Thermionic Emission, Multielectron Bubbles, and A Novel Electron Collector in a Liquid Helium Environment

J. Fang·Anatoly E. Dementyev·Jacques Tempere·Isaac F. Silvera
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Abstract

We study two techniques to create electrons in a liquid helium environment. One is thermionic emission of tungsten filaments in a low temperature cell in the vapor phase with a superfluid helium film covering all surfaces; the other is operating a glowing filament immersed in bulk liquid helium. We present both the steady state and rapid sweep I-V curves and the electron current yield. These curves, having a negative dynamic resistance region, differ remarkably from those of a vacuum tube filament. A novel low temperature vapor-phase electron collector for which the insulating helium film on the collector surface can be removed is used to measure emission current. We also discuss our achievement of producing multi-electron bubbles (MEBs) in liquid helium by a new method.

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J. Fang, Anatoly E. Dementyev, Jacques Tempere, Isaac F. Silvera. 2008-12-24. Thermionic Emission, Multielectron Bubbles, and A Novel Electron Collector in a Liquid Helium Environment. https://doi.org/10.1063/1.3103944

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