1. System overview:

This document summarizes essential details for materials, setup, and operation. This is for transcription, archival, and research purposes only. It is based on an old patent and is not intended as a finished product. Operating conditions described require specialized handling and safety precautions, and the descriptions outlined here do not constitute a recommendation or endorsement to build or operate the device. Attempts to replicate or build upon these models are entirely at your own risk.

Source patent:

• Shoulders, Kenneth R. U.S. Patent No. 5,123,039. Issued June 16, 1992.
• Image: Figure 49
• Text: FROM Column 42 line 37 UNTIL Column 44 line 4

1.1. Purpose

Basic Function:
The electrodeless EV source can be used when you want EVs without cathode residue in the emission, or when you want to use RF power to generate them. They don't emit from a metal electrode tip, but rather through field effects on the inside of a dielectric envelope, where strong RF dissociates a gas and generates one or more EVs out of it.

Core Behavior:
Auxiliary gas ports and guide elements for formed EVs are not shown. The envelope is supposed to contain a high-polarizability gas (i.e., xenon) which due to the shape of the two formation electrodes and the RF waves emanating from them will experience breakdown at the tip of the dielectric. Here, the breakdown won't consist of taylor cones of electrons on top of a cathode, but rather an electron/xenon-ion plasma where the more mobile electrons form an EV. This process for forming EVs generates EVs and plasmas that are different in composition than normal: since there is no injection of electrons into the medium, the plasma on average remains neutral, with negative EVs along the center of a thin streamer, surrounded by a cloud of positive ions. These streamers form along the surface of the dielectric. The first EV to run along such a streamer creates the charge-separated double-layer and subsequent EVs can travel through the same streamer without performing more charge-separation. If a gas pressure differential is set up between the two compartments, and the second compartment is at a sufficiently low gas pressure, it may not be able to create streamers and instead propagate as a "black EV".

Scale & Format:
A small dielectric tube with a constriction. Either end (542 and/or 544) can be fitted with auxiliary ports for gas input or exit, as well as 544 being fitted with a guide element to guide EVs away with. Example dimensions for one range of parameters is given, with 0.05 mm as the constriction aperture. The example provided for this object may be a few millimeters in length, and close to a millimeter (0.8) in diameter, though in the description it is clear that the dimensions may be altered and the same principle may even be made into a laminar device.

1.2. Components

Diagram(s):

Parts list:

Notes:
This device may be made through sintering several easier shapes of alumina together, followed by the application of silver paste for the electrodes.

2. Device materials and environment

2.1. Materials

Suggested Materials:

• The envelope should be made of alumina or another strong dielectric
• The electrodes may be painted silver paste
• The inner volumes of the dielectric envelope should be filled with ~0.1 atmospheres of Xenon

2.2. Operating Conditions

The device as shown in this document is based on descriptions given in the patent. While the description of the device made it clear that a lot of parameters could be altered, it did describe an example and pretty clear parameter space for it to be used in. The following description is for the example device as described, though not the one illustrated, as several proportions in the figure and description contradict. This will be highlighted.

Electrical:

• Bipolar (i.e. RF) electrical energy should be applied to electrodes 534 and 536, the formation and intermediate ring electrodes.
  • A 3kV peak-to-peak voltage difference between the two electrodes is described.
  • This is in relation to the 0.1 Atmospheres of xenon in the formation chamber.
  • This is also in relation to the 0.25 mm thick dielectric (the description and figure contradict here, the model only has 0.15mm thick dielectric).
  • This is also in relation to the 50 micrometer aperture separating the chambers.
  • Frequency of the RF energy is not mentioned.
• The extraction electrode (538) may be operated at relatively positive voltages for extraction, dynamically offset in a way which takes the voltage of the intermediate ring electrode into account.

Environment:

• The pressure in this device by default would be 0.1 atmospheres of xenon.
• By appropriate pumping to the formation chamber and away from the exploitation chamber, and a sufficiently constrictive aperture, a pressure differential can be created leading to an exploitation chamber of lower pressure, in which it is easier to manipulate the EVs outside of streamers. No specific pressure values are given for this "sufficiently low to inhibit streamers" condition.

3. Additional information

3.1. Additional information

It is unclear what causes EVs to go black. It can be inferred from the description in the patent of the formation of black EVs that it may not be the EVs that go black, as much as the EV never having been light to begin with save the matter it interacts with or the electrons it ejects. In the electrodeless emitter, there may not be a large excess of electrons as there is in the case of formation from a cathode's negative pulse taylor cones or field emission, leading to an EV that would, save the EM interaction with matter around it, not have any means of emitting light. Not through radiation emitted by interactions of unbound excess electrons, nor by the induction generated by an EV passing through a gas. This mention is interesting, as it is described as a reproducible feature which may have applications, which implies that at the very least these versions of dark EVs can still be controlled. This contrasts strongly with dark EVs as mentioned in EV a tale of discovery (page 69, "Enter the Black EV"), where a volume of "low pressure hydrogen" gets compared to "the vacuum case", where in the low pressure hydrogen EVs would go black whereas in the vacuum case the EVs would not go black. This seems to imply that whatever makes EVs emitted through a negative cathode pulse (with an excess of electrons) glow gets diminished by interaction with too much matter, whereas the glow of EVs emitted in this electrodeless emission process gets diminished by not having matter to interact with.

3.2. Attachments

• Figures 49
• Electrodeless sources
• Electrodeless.FCStd
• Electrodeless.stl
• Electrodeless_annotated.FCStd