Physics

Electron

Transverse plane

Maser

Structural engineering

Terahertz radiation

Magnetic field

Optics

Harmonic

Engineering

Acoustics

Nuclear physics

Gyrotron

Nuclear magnetic resonance

Quantum mechanics

Cyclotron

IEEE Electron Device Letters

A method of increasing the selectivity of highly-oversized open cavities is experimentally demonstrated in the electron cyclotron maser (gyrotron) operating at the second cyclotron harmonic in a high transverse mode (presumably, TE58,13) of a circular cylindrical cavity at a frequency near 1.2 THz in the magnetic field of 24 T. This method is purely electrodynamical and based on a simple deformation of the cavity wall. The proposed approach paves the way for increase of the gyrotron frequencies and for enhancing the selectivity of open cavities in other applications.

Demonstration of a Selective Oversized Cavity in a Terahertz Second-Harmonic Gyrotron