Gyrotron
vacuum tube which generates high-frequency radio waves
A gyrotron is a class of high-power linear-beam vacuum tubes that generates millimeter-wave electromagnetic waves by the cyclotron resonance of electrons in a strong magnetic field. Output frequencies range from about 20 to 527 GHz, covering wavelengths from microwave to the edge of the terahertz gap. Typical output powers range from tens of kilowatts to 1–2 megawatts. Gyrotrons can be designed for pulsed or continuous operation. The gyrotron was invented by Soviet scientists at NIRFI, based in Nizhny Novgorod, Russia.
Principle
The gyrotron is a type of free-electron maser that generates high-frequency electromagnetic radiation by stimulated cyclotron resonance of electrons moving through a strong magnetic field. It can produce high power at millimeter wavelengths because, as a fast-wave device, its dimensions can be much larger than the wavelength of the radiation. This is unlike conventional microwave vacuum tubes such as klystrons and magnetrons, in which the wavelength is determined by a single-mode resonant cavity, a slow-wave structure. Thus, as operating frequencies increase, the resonant cavity structures must decrease in size, which limits their power-handling capability.
In the gyrotron, a hot filament in an electron gun (1) at one end of the tube emits an annular-shaped (hollow tubular) beam of electrons (6), which is accelerated by a high-voltage DC anode and then travels through a large tubular resonant cavity structure (2) in a strong axial magnetic field, usually created by a superconducting magnet around the tube (8).
The public source identifies “Gyrotron” as vacuum tube which generates high-frequency radio waves. This brief keeps that definition visible, then builds a research path around Gyrotron, vacuum and tube.
Why this record matters
A short description can identify a subject without explaining its stakes. For “Gyrotron”, the useful work is to connect “vacuum tube which generates high-frequency radio waves” to the records capable of establishing context and consequence.
Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Sep 15, 2026. The linked authority identifier is Q1254606. None of the 0 selected statements returned an explicit reference.
A concise general-reference account can conceal disagreements about scope, terminology or the weight assigned to individual sources. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.
- Subject orientation
- Search vocabulary
- Locating named sources
The closest primary source, responsible institution and strongest cited specialist reference.
Three-step research path
- Establish the record: confirm the title “Gyrotron”, its source revision and the description used here.
- Expand the search: follow Gyrotron primary sources, Gyrotron archive and Gyrotron research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Gyrotron”?
- What terminology or title could unlock a more precise catalogue search?
- Which institution is responsible for the underlying evidence?
Search terms from this dossier
This entry incorporates text from “Gyrotron” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.