Demonstration of microwave generation by a ferroelectric-cathode tube

A ferroelectric cathode is employed in a cyclotron-resonance maser (CRM). T he CRM oscillator device operates at similar to 7 GHz, near the cutoff freq uency of a hollow cylindrical cavity. The cathode is made of a PLZT 12/65/3 5 ceramic with high-dielectric constant (epsilon(r)similar to 4000). Electr ons are extracted from the plasma excited on the cathode surface by similar to 1 kV short rise-time pulses. The use of ferroelectric cathodes may adva nce the microwave tube technology for various applications. (C) 1999 Americ an Institute of Physics. [S0003-6951(99)03403-8].